Device and method for delivering an oral care agent

ABSTRACT

An oral care agent delivery device is provided which comprises a permanently deformable backing layer, an oral care layer, and a non-woven binding material with a first part that is substantially invested in the oral care layer and a second part that is substantially invested in the backing layer. The device is sized to fit over a plurality of teeth in an upper or lower dental arch of a subject. The oral care layer comprises at least one oral care agent and at least one hydrophilic polymer. When hydrated, the oral care layer has an adhesiveness relative to the surface of a user&#39;s teeth that is sufficient to retain the device on the user&#39;s teeth when placed thereon. The device can also have an oral care agent which is activated on hydration of the oral care layer, or an oral care layer which releases the oral care agent over time.

FIELD OF THE INVENTION

This invention relates to the field of delivering an oral care agent,especially a tooth whitening agent, with a dental device.

BACKGROUND OF THE INVENTION

A variety of devices and methods have been developed to deliver atherapeutic or cosmetic agent to surfaces in the oral cavity. Inparticular, many systems which deliver a whitening agent to the teethare available.

A person desiring whiter teeth can choose from professional whiteningsystems, or can purchase an over-the-counter tooth whitening device foruse in the home. In the professional teeth bleaching market, dentistshave traditionally used devices for delivery of home bleaching agentswhich are rigid and custom-fitted to an individual patient's dentalarches. One type of delivery device is molded to closely fit a patient'sdental arches. Another type of device is an “oversized” rigid customdental appliance, which is formed by augmenting the facial surfaces ofthe teeth on stone models made from the patients' teeth, for examplewith linings such as die spacers or light-cured acrylics. A third typeof device is a rigid, bilaminated custom-made dental appliancefabricated from materials ranging from soft porous foams to rigid,non-porous films. The non-porous, rigid thermoplastic shells of suchbilaminated dental appliances may encase and support an internal layerof soft, porous foam which absorbs the bleaching agent.

After the custom appliance is fabricated, the dentist typically deliversthe first bleaching treatment in the office, and instructs the patienton the proper procedure to dispense bleaching agent in the customappliance at home. A sufficient amount of bleaching agent is provided sothat the patient can perform the prescribed home bleaching regimen. Thepatient subsequently applies the bleaching agent daily (or as otherwiseinstructed) by dispensing the bleaching agent into the rigid customdental appliance and placing the appliance over the dental arch for aspecified period of time. At the end of a given treatment period, thedental appliance is removed, thoroughly cleaned to remove any remainingbleaching agent, and stored until the next application. The professionaltooth whitening systems generally use a higher concentration ofbleaching agent, and consequently the overall treatment period isshorter than that recommended for over-the-counter systems.

However, the rigid, custom-fabricated dental appliances used inprofessional tooth whitening systems require time-consuming andexpensive office visits, laboratory tests and the fitting of eachpatient's dentition. Furthermore, any changes in the surface of thepatient's teeth (such as fillings, crowns, and other accidental ortherapeutic alterations of the dentition) affect the fit of the rigidcustom dental appliance, and may warrant repeating the entirefabrication procedure. Refabrication of the appliance may also berequired in the event of subsequent rebleaching treatments.

Moreover, patients who are inexperienced and unaware of the importanceof precision often dispense an improper amount of bleaching agent intothe appliance. Dispensing too little bleaching agent into the deviceresults in a less efficacious treatment regimen. Dispensing an excessiveamount of bleaching agent into the appliance can cause the agent to bedisplaced from the appliance into the oral cavity when the device isplaced on the teeth, where the agent can be ingested. In addition tosuch displacement, the bleaching agent can spill or leak from theseappliances into the oral cavity, causing, for example, an unpleasanttaste sensation, gingival irritation, burning, edema, nausea or allergicreactions. The risk of the more serious side effects increases with thenumber of treatments, and becomes most significant after the multipletreatments typically required to attain acceptable clinical results.Patients who self-administer bleaching or other medicinal agents mayalso fail to provide the careful maintenance, cleaning, and storagenecessary to ensure that the rigid custom dental appliance performsadequately throughout its entire service life.

There are additional drawbacks with custom bilaminated dentalappliances, including occlusion and retention of bleaching agent.Furthermore, cleaning and maintenance of foam-lined dental appliancesmay be problematic, due to the high surface area and pore volume of thefoam materials typically used in such appliances.

Oversized rigid custom dental appliances also have additional drawbacks,including occlusions in the augmented region, increased appliancefabrication time and cost, irritation from the lip of the appliancecontacting the gingival region, and decreased retention of the bleachingagent within the target area.

In order to avoid the high cost and inconvenience of professional toothwhitening systems, one may purchase non-professional, “over-the-counter”tooth whitening systems. Some versions of the over-the-counter systemscontain a generic “one size fits all” appliance and a container ofbleaching gel to be dispensed into the appliance, for example asdescribed in U.S. Pat. No. 3,416,527 of Greenberg and U.S. Pat. No3,527,219 of Hoef. However, such generic appliances often have a greatervoid between the interior walls of the appliance and the teeth ascompared to most professionally fitted appliances. Hence, in order toinsure intimate contact of the bleaching agent and the teeth surfaces,more bleaching agent is required. Furthermore, the poorer fit of thegeneric device means a greater loss of bleaching gel into the oralcavity, with the attendant problems described above for the professionaltooth whitening appliances. Thus, the leakage problems of professionaltooth whitening systems are exacerbated by over-the-counter systems inwhich the user dispenses the whitening agent into the device. Thegeneric over-the-counter devices also tend to be bulky and uncomfortablein the mouth.

Over-the-counter systems with pre-dispensed bleaching agent are alsoavailable. The bleaching agents used in such over-the-counter systemsare either viscous liquids or gels containing peroxide compounds. Theperoxide compounds are typically provided in hydrated (i.e., active)form, or the peroxide compounds become hydrated due to moisture in theagent or the surrounding air. A typical bleaching agent is a carbamideperoxide gel, in which hydrogen peroxide is coupled to urea in either ananhydrous glycerin base or a soluble, aqueous carboxylic acid polymerbase. Upon hydration, the carbamide peroxide breaks down into urea andactive peroxide. The active peroxide subsequently breaks down into waterand oxygen. Over time, the inherent instability of hydrated peroxidebleaching agents reduces the efficacy of tooth whitening systems withpre-dispensed bleaching agents. The shelf-life of such systems istherefore limited.

U.S. Pat. No. 5,310,563 of Curtis et al. discloses an over-the-countertooth whitening device in which a putty-like material encapsulating thebleaching agent is molded around the teeth. The putty is held in placeby mechanical engagement with undercut surfaces of the teeth, and byfriction. The bleaching agent migrates from the composition to the gumsand tooth surfaces, rather than being directly in contact with them,which significantly increases the required wearing time. The putty alsotends to slip off the teeth, further reducing the efficacy of this typeof system.

U.S. Pat. Nos. 5,575,654 and 5,863,202 of Fontenot disclose anover-the-counter tooth whitening system containing prepackaged moldabledental appliance that can be adapted to fit the dental arch, whichcontains a premeasured amount of medicinal or bleaching agent. It hasbeen observed that the Fontenot device frequently has the problems ofbulk and compromised fit. The pressure required to mold the device tothe dental arch can also force the bleaching agent out of the device andinto the oral cavity.

U.S. Pat. No. 5,980,249 of Fontenot describes a whitening systemconsisting of a prefabricated, U-shaped dental appliance of hydrophilicfoam. The bleaching agent is incorporated or invested in the foam. Thisdevice has drawbacks similar to those described above for professionaltooth whitening systems using custom bilaminated dental devices. Suchdrawbacks include occlusion and retention of bleaching agent in thefoam, and extrusion of the bleaching agent into the oral cavity uponapplication of the pressure required to form the device to the user'steeth.

U.S. Pat. Nos. 5,879,691, 5,891,453 and 5,894,017 of Sagel et al.describe over-the-counter tooth whitening systems consisting of flat,flexible strips coated on one surface with an adhesive gel containing ableaching agent. The strips are meant to be folded over the teeth by theuser, with the bleaching agent in contact with, and holding the deviceonto, the teeth. However, the strip does not adhere well to the toothsurface, and the device tends to slip off the teeth in use.

The bleaching gel is also poorly attached to the Sagel et al. flexiblestrip, and often adheres to the user's fingers during the manipulationsrequired to fold the strip in place over the dental arch. The potentialfor contamination of the strip by the user's fingers during routinemanipulation is high. Moreover, the bleaching gel can be transferredfrom the user's fingers to the clothes (which may then be stained orbleached), or to sensitive areas of the body like the eyes, which maycause extreme discomfort. The bleaching gel will also adhere to itselfand delaminate from the flexible strip if the user inadvertently foldsthe strip in upon itself during placement onto the teeth. Suchdelamination of the bleaching gel reduces the efficacy of the whiteningsystem. Upon removal of the Sagel et al. strip from the teeth, aquantity of the bleaching agent can also adhere to the teeth. Thisleftover bleaching agent leaves an unpleasant taste in the mouth, and iseasily ingested.

Moreover, most of the bleaching gel content of the Sagel et al. strip isdelivered and begins to degrade as soon as the strip is placed in themouth, resulting in reduced efficacy of the whitening system. Repeatedand prolonged use of the Sagel et al. strips is thus required to achievethe desired whitening effect.

Over-the-counter whitening systems similar to those described in theSagel et al. patents are disclosed in U.S. Pat. Nos. 5,989,569 and6,045,811 of Dirksing et al. The Dirksing et al. system consists of adeformable flat wax strip carrying the same type of bleaching gel as theSagel et al. strips. Here again, the bleaching gel is poorly adhered tothe wax strips, and the Dirksing et al. system likely suffers from thesame problems of difficulty of use and reduced efficacy as describedabove for the Sagel et al. strips.

U.S. Pat. App. 2004/0005277 of Willison et al. describesover-the-counter tooth whitening systems comprising a permanentlydeformable backing layer, a foam anchor layer and an oral care layercomprising a medicament such as a bleaching agent. This device overcomessome of the problems associated with the above-described knowninventions. The device is less bulky than the pre-formed over thecounter devices, but still has a substantial bulk due to the thicknessof the foam anchor layer. The bulk causes potential comfort andconformability problems. The bulk also adds to the expense of the diecutting operations used in making the devices. In addition, the foamanchor layer readily absorbs water, thereby diluting the oral careactive, which in turn may reduce the efficacy of the device. The layeredstructure of the device increases the possibility of delamination duringuse or removal. For example, when a user removes the device, the oralcare layer may continue to adhere to the surface of the teeth,separating from the wax backing layer and/or the foam anchor layer.

Many of the known professional and over-the-counter tooth whiteningsystems can also be used to deliver other oral care agents, such asmedicines or antibiotics, to the teeth and gingival tissue. However, thedrawbacks described above for the tooth whitening systems are alsopresent when the systems are used to deliver other oral care agents.

What is needed, therefore, is an over-the-counter device for deliveringan oral care agent, for example a tooth whitening agent, in which apre-measured amount of oral care agent is contained within a device thatis firmly held onto a user's teeth, which does not release the oral careagent into the oral cavity in appreciable quantities, which isrelatively non-bulky in structure, and which does not delaminate duringuse or removal. The device should also be configured so that the userdoes not contact the oral care agent during routine manipulation of thedevice into place over the dental arch. The layer which delivers theoral care agent should also be sufficiently secured to the device sothat little or no residue is left on the user's fingers if the layer isinadvertently touched, and no residue is left on the teeth upon removalof the device. Furthermore, the oral care agent should be activated andreleased from the device over time, so that efficacy of the agent ismaximized and not diluted, and the number and duration of eachapplication is reduced.

SUMMARY OF THE INVENTION

It has been found that the deficiencies of both the professional andover-the-counter oral care agent delivery systems discussed above areovercome by the oral care agent delivery devices of the invention.

The device of the invention comprises a permanently deformable backinglayer, a non-woven binding material comprising a first part and a secondpart, and an oral care layer. The device is sized to fit over aplurality of teeth in an upper or lower dental arch of a subject. Theoral care layer comprises at least one oral care agent and at least onehydrophilic polymer. The binding material is a non-woven material thatbinds the oral care layer and the backing layer. The first part of thebinding material is substantially invested in at least a portion of theoral care layer, and the second part of the binding material issubstantially invested in at least a portion of the backing layer. Theoral care layer has an adhesiveness when hydrated relative to thesurface of the teeth of wearer that is sufficient to retain the deviceon the user's teeth when placed thereon.

The invention also provides a device that has a substantially non-flatcross section.

The invention also provides a device in which the oral care agent isactivated on hydration of the oral care layer.

The invention also provides a device comprising a sustained release oralcare layer.

The invention also provides a method for delivering an oral care agentto a plurality of teeth in an upper or lower dental arch in a subject,comprising providing a device which comprises a permanently deformablebacking layer, a non-woven binding material with a first part and asecond part, and an oral care layer. The device is sized to fit over aplurality of teeth in an upper or lower dental arch of a subject. Theoral care layer comprises at least one oral care agent and at least onehydrophilic polymer. The first part of the binding material issubstantially invested in at least a portion of the oral care layer, andthe second part of the binding material is substantially invested in atleast a portion of the backing layer. The oral care layer has anadhesiveness when hydrated relative to the surface of the teeth of awearer that is sufficient to retain the device on the wearer's teethwhen placed thereon. The oral care agent is delivered by wetting theteeth or the oral care layer, placing the device over the teeth of adental arch, and pressing the device to the teeth by manual pressure sothat the oral care layer is in contact with at least the front surfaceof the teeth. The device is then left on the teeth for a sufficient timeto achieve the desired result, whereupon it is removed from the teethand discarded. The process of delivering the oral care agent can berepeated as necessary.

The invention further provides a method for delivering a tooth whiteningagent to a plurality of teeth in an upper or lower dental arch in asubject, comprising providing a device comprising a permanentlydeformable backing layer, a non-woven binding material with a first partand a second part, and an oral care layer. The device is sized to fitover a plurality of teeth in an upper or lower dental arch of a subject.The oral care layer comprises at least one oral care agent and at leastone hydrophilic polymer. The first part of the binding material issubstantially invested in at least a portion of the oral care layer, andthe second part of the binding material is substantially invested in atleast a portion of the backing layer. The oral care layer has anadhesiveness when hydrated relative to the surface of the teeth of awearer that is sufficient to retain the device on the wearer's teethwhen placed thereon. The tooth whitening agent is delivered by wettingthe teeth or the device, pressing the device over the teeth, andpressing the device to the teeth by manual pressure so that the oralcare layer is in contact with at least the front surface of the teeth.The device is then left on the teeth for a sufficient time to achievethe desired result whereupon it is removed from the teeth and discarded.The process of delivering the tooth whitening agent can be repeated asnecessary.

The invention further provides a method of making a device fordelivering an oral care agent, which device comprises a permanentlydeformable backing layer, a non-woven binding material with a first partand a second part, and an oral care layer. The method comprises thesteps of providing the permanently deformable backing layer, pressingthe binding material into the backing layer such that the second part ofthe binding material substantially invests in at least a portion of thebacking layer, and extruding the oral care layer onto the bindingmaterial such that the first part of the binding material substantiallyinvests in at least a portion of the oral care layer.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an isometric view of one embodiment of a device of theinvention as seen from the back.

FIG. 2 is an isometric view of the device of FIG. 1 as seen from thefront.

FIG. 3 is a top plan view of the of the device of FIG. 1.

FIG. 4 is a back view of the device of FIG. 1.

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 3.

FIG. 5A is an exaggerated view of a portion of the cross-section of FIG.5.

FIG. 6 is a top plan view of a flattened form of the device of FIG. 1.

FIG. 7 is an isometric view of another embodiment of a device of theinvention as seen from the back.

FIG. 8 is top plan view of a flattened form of the device of FIG. 7.

FIG. 9 is a back view of the device of FIG. 7.

FIG. 10 is a cross-sectional view taken along line 10-10 of FIG. 9.

FIG. 11 is a top plan view of a flattened form of a further embodimentof a device of the invention.

FIG. 12 is a top plan view of a flattened form of a further embodimentof a device of the invention.

FIG. 13 is a top plan view of a flattened form of a further embodimentof a device of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention concerns devices which deliver an oral care agent to thesurface of the teeth. The present devices are particularly well-suitedto delivering a tooth whitening agent to the surface of the teeth.

The construction of the device, and the characteristics of the variouslayers which comprise the device, serve to overcome the disadvantages ofprior commercial or over-the-counter delivery systems discussed above.For example, the present device contains a pre-measured amount of oralcare agent in an oral care layer, so there is no danger of over- orunder-filling by the user. Because the oral care agent is not dispensedinto the device by the user, the chance of contamination of the oralcare layer by improper or careless filling of the device is eliminated.Moreover, the physical characteristics of the oral care layer are suchthat oral care agent does not spill or squeeze out into the oral cavityin appreciable quantities when the device is placed on the teeth.

The present device can be configured so that the user does not contactthe oral care agent during routine manipulation of the device into placeover the dental arch, but rather contacts only the backing layer. In anyevent, the oral care layer is sufficiently secured to the device by anon-woven binding material so that no residue is left on the user'sfingers if the oral care layer is inadvertently touched. Moreover, no orminimal residue of the oral care layer is left on the teeth upon removalof the device. In some embodiments, as discussed in more detail below,the oral care agent is activated and/or released from the oral carelayer over time, so that efficacy of the agent is maximized and thenumber and duration of each application is reduced.

All percentages given herein are by weight.

The device of the invention comprises two layers: a permanentlydeformable backing layer and an oral care layer. The two layerspreferably are in contact with one another and preferable form anadhesive bond at the contact point. The two layers are further heldtogether by a non-woven binding material. As used herein a non-wovenbinding material is a non-woven material that binds two or morechemicals, or two or more layers together through physical, mechanicalor chemical means. The binding material of the invention comprises afirst part and a second part. The first part of the binding material issubstantially invested in the oral care layer and the second part of thebinding material is substantially invested in the backing layer. Thebinding material preferably does not create a separate layer. Rather, atleast a portion of the binding material is invested in the oral carelayer and at least a portion of the binding material is invested in thebacking layer, and there is no portion of the binding material that isnot invested in either the oral care layer or the backing layer. Theintended result is a device with two layers, the oral care layer and thebacking layer, in contact with one another and forming an adhesive bondthere between with the binding material aiding in the adhesive stabilityof the bond.

The backing layer comprises a thin, flexible layer of permanentlydeformable material. As used herein “permanently deformable” means thatthe backing layer retains any shape into which it is formed byapplication of slight pressure e.g., less than about 250,000 Pascals persquare centimeter. Thus, the device readily conforms to the surface ofthe teeth and adjoining soft tissue across the dental arch in the user'smouth without tearing, cracking or breaking. The material whichcomprises the backing layer preferably has visco-elastic propertieswhich allow the backing layer to creep as well as bend when pressure isapplied to the device.

For example, a user can form the device around the teeth of the upper orlower dental arch by applying normal manual pressure to the backinglayer with the tips of the fingers and thumbs. Assuming the surface areaof the average adult finger or thumb tip is approximately one squarecentimeter, the normal pressure generated by the finger and thumb tipsis about 100,000 to about 150,000 Pascals (i.e., about 3 lbs. or 1.36kg) per square centimeter. The pressure is typically applied to thedevice by each finger and thumb tip for about one or two seconds. Oncethe pressure applied to the backing layer by the tips of the fingers andthumbs is removed, the device retains the shape of the dental arch andsurface of the teeth and adjoining soft tissue onto which it was formed.

As used herein, “adjoining soft tissue” means the tissue surrounding thetooth structure, including the marginal gingiva, gingival sulculus,inter-dental gingiva, and the gingival gum structure on the lingual andbuccal surfaces up to and including the muco-gingival junction and thepallet.

The backing layer can be any thickness that allows it to retain itspermanently deformable characteristics; i.e., the layer cannot be sothin as to fail to retain its shape after application of pressure, andthe layer cannot be so thick as to resist deformation. Preferably, thebacking layer is from about 0.025 mm (1 mil) to about 0.508 mm (20 mils)thick, more preferably about 0.125 mm (5 mil) to about 0.457 mm (18 mil)thick, and particularly preferably about 0.38 mm (15 mil) thick.

The backing layer preferably comprises a non-polymeric material such asa wax (e.g., microcrystalline or paraffin waxes), a tackifier (e.g., anatural or synthetic resin, such as a hydrocarbon resin), or mixturesthereof that have the properties discussed above.

Paraffin waxes are low-molecular weight waxes composed of straight-chainhydrocarbons, with melting points ranging from 48° C. to 75° C. Thesewaxes are typically highly refined and have a low oil content. Theparaffin waxes can be obtained by the distillation of crude oil, or canbe produced synthetically, for example by Fischer-Tropsch synthesis.Paraffins produced by Fischer-Tropsch synthesis contain straight chainhydrocarbon molecules comprising methylene groups, which may have eithereven or odd numbers of carbons. The synthetic paraffins typically have amolecular weight range from about 300 g/mol to about 1400 g/mol, andmelting points of about 48° C. to 75° C.

Microcrystalline waxes are flexible and amorphous-like in appearance,and have a higher tensile strength and smaller crystals than theparaffin waxes. The molecular weight of the commercially availablemicrocrystalline waxes is generally from about 580-700 g/mol, with theaverage molecule containing 41-50 carbon atoms. Straight-chain moleculesmay be present in the microcrystalline waxes, but the largest proportionof molecules are branched-chain hydrocarbons and some ring-typecompounds. The melting point of microcrystalline waxes is typicallyhigher than the paraffin waxes; e.g., from about 60° C. to about 95° C.

Preferred microcrystalline and paraffin waxes for use in the presentinvention, and their physical characteristics, are given below inTable 1. A particularly preferred wax is Microcrystalline 180/185(#146), available from Koster-Keunen, Inc., Watertown, Conn., 06795.Other suitable waxes include #165 sheet wax, available from Freeman Mfg.& Supply Co., Avon, Ohio, 44011-1011. TABLE 1 Congealing AcidSaponification Oil Content Point Melting Value Value PenetrationViscosity (wt %; Color Wax (ASTM D938) Point (USP 401) (USP 401) (ASTMD1321) (ASTM D2161) ASTM D721) (Visual) Microcrystalline 77-81° C.77-85° C. <1 <1 10-16, 100 g, 70-84@ 99° C. 1.5% max white to 180/185(#146)¹ 5 s, @25° C. light yellow Microcrystalline 80-92° C. 89-92° C.<1 <1 5-9, 100 g, — — light yellow 193/198 (#118P)¹ 5 s, @25° C.Paraffin 82-92° C. 60-63° C. 0.1 max 0.1 max 11-18, 100 g, — 1.5% max —140/145 (#126G)¹ 5 s, @25° C. Microcrystalline — 82-88° C. Nil Nil13-19, 100 g, 75-90@ 99° C. — yellow Wax S.P. 16² 5 s, @25° C. syntheticparaffin¹ 78-105° C. — — — — — not greater white (CAS 8002-74-2) than0.75%¹Available from Koster-Keunen, Inc., Watertown, CT, 06795.²Available from Strahl & Pitsch, Inc., West Babylon, NY, 11704.

The backing layer can also comprise hydrocarbon resins. Hydrocarbonresins are amorphous, glassy, typically low molecular weighthydrocarbons with defined molecular weight ranges. Hydrocarbon resinssuitable for producing the backing layer include the “Escorez” 5300series of water-white, clear cycloaliphatic hydrocarbon resins (CAS#68132-00-3) available from ExxonMobil Chemical, Houston, Tex.77079-1398. A preferred hydrocarbon resin is Escorez 5380. The typicalphysical characteristics of the Escorez 5300 series hydrocarbon resinsare given in Table 2 below. TABLE 2 Resin ExxonMobil 5380 5300 5320 5340Test Method² Softening Point, 85 105 122 140 ETM 22-24 R&B, ° C. ColorYlt, initial¹ 1 1 1 1 ETM 22-13 Yl, Aged 5 hours 3 3 3 3 ETM 22-14 at175° C.¹ Molten Gardner 1 1 1 1 ETM 22-12 Color Melt Viscosity ETM 22-31(Brookfield) Test Temperature, 140 140 160 180 ° C. Cps 700 4,500 5,0004,500 Molecular Weight ETM 300-83 {overscore (M)}w 370 420 430 460{overscore (Mn)} 160 210 190 230 {overscore (Mz)} 900 900 950 1000 Tg, °C. 35 55 65 85 ETM 300-90 Specific Gravity, 1.1 1.1 1.1 1.1 ETM 22-2820/20° C. (IPOH) Ash Content, <0.1 <0.1 <0.1 <0.1 ETM 22-05 wt. % AcidNumber, <1 <1 <1 <1 ETM 22-49 mg KOH/g Volatility, wt % 10.0 4.0 1.5 0.5ETM 22-32¹Solution color as determined by measurement of a 50% (by weight)product in toluene mixture.²The entire disclosures of the ExxonMobil Test Methods are hereinincorporated by reference.

The backing layer can optionally be colored, so that the device isvisibly obtrusive when worn. For example, the backing layer (and thusthe device itself) can be colored with bright or vibrant colors which aconsumer may find pleasing. The backing layer can therefore comprise acolorizing compound, such as, for example, a dye, pigment or substancethat can impart color when added to the material forming the backinglayer.

For example, colorizing compounds of the type commonly used with foods,drugs, or cosmetics in connection with the human body, especially coloradditives permitted for use in foods which are classified as“certifiable” or “exempt from certification,” can be used to color thebacking layer. The colorizing compounds used to color the backing layercan be derived from natural sources such as vegetables, minerals oranimals, or can be man-made counterparts of natural derivatives.

Colorizing compounds presently certified under the Food Drug & CosmeticAct for use in food and ingested drugs include dyes such as FD&C Red No.3 (sodium salt of tetraiodofluorescein); Food Red 17 (disodium salt of6-hydroxy-5-{(2-methoxy-5-methyl-4-sulphophenyl)azo}-2-naphthalenesulfon-icacid); Food Yellow 13 (sodium salt of a mixture of the mono anddisulfonic acids of quinophthalone or 2-(2-quinolyl)indanedione); FD&CYellow No. 5 (sodium salt of4-p-sulfophenylazo-1-p-sulfophenyl-5-hydroxypyrazole-3 carboxylic acid);FD&C Yellow No. 6 (sodium salt ofp-sulfophenylazo-B-napthol-6-monosulfonate); FD&C Green No. 3 (disodiumsalt of4-{[4-(N-ethyl-p-sulfobenzylamino)-phenyl]-(4-hydroxy-2-sulfonium-phenyl)-methylene}-[1-(N-ethyl-N-p-sulfobenzyl)-3,5-cyclohexadienimine]);FD&C Blue No. 1 (disodium salt ofdibenzyldiethyl-diaminotriphenylcarbinol trisulfonic acid anhydrite);FD&C Blue No. 2 (sodium salt of disulfonic acid of indigotin); FD&C RedNo. 40; Orange B; and Citrus Red No. 2; and combinations thereof invarious proportions.

Colorizing compounds exempt from FDA certification include annattoextract; beta-apo-8′-carotenal; beta-carotene; beet powder;canthaxanthin; caramel color; carrot oil; cochineal extract (carmine);toasted, partially defatted, cooked cottonseed flour; ferrous gluconate;fruit juice; grape color extract; grape skin extract (enocianina);paprika; paprika oleoresin; riboflavin; saffron; turmeric; turmericoleoresin; vegetable juice; and combinations thereof in variousproportions.

The form of the colorizing compound for use in the present inventionpreferably includes dye form additives, but may also include lake formswhich are compatible with the material comprising the backing layer.Water soluble dyes, provided in the form of powders, granules, liquidsor other special-purpose forms, can be used in accordance with thepresent method. Preferably, the “lake”, or water insoluble form of thedye, is used for coloring the backing layer. Lake form additives arepreferred over straight dyes because of their greater stability andlesser tendency to color bleed. For example, if a suspension of acolorizing compound is to be used, a lake form additive can be employed.Suitable water insoluble dye lakes prepared by extending calcium oraluminum salts of FD&C dyes on alumina include FD&C Green #1 lake, FD&CBlue #2 lake, FD&C RED #30 lake and FD&C # Yellow 15 lake.

Other suitable colorizing compounds include non-toxic, water insolubleinorganic pigments such as titanium dioxide; chromium oxide greens;ultramarine blues and pinks; and ferric oxides. Such pigments preferablyhave a particle size in the range of about 5 to about 1000 microns, morepreferably about 250 to about 500 microns.

The concentration of the colorizing compound in the backing layer ispreferably from about 0.05% to about 10%, and is more preferably fromabout 0.1% to about 5%.

More than one colorizing compound can be present in the backing layer,so that multiple colors are imparted to the backing layer. The multiplecolors in the backing layer can be patterned into stripes, dots, swirlsor any other design which a consumer may find pleasing. The colorizingcompound can also be used with other appearance-enhancing substancessuch as glitter particles.

The backing layer can also be embedded or decorated with decorativeitems such as beads, rhinestones, or the like, as long as these items donot interfere with the properties of the backing layer required forproper deformation of the device onto the teeth, as described above. Thebacking layer can also display letters, words, or images designed to bepleasing or attractive to a consumer.

The backing layer can also comprise additional ingredients includingcoloring compounds as described above; food additives; flavorants;sweeteners; and preservatives.

Any natural or synthetic flavorant or food additive, such as thosedescribed in Chemicals Used in Food Processing, Pub. No. 1274, NationalAcademy of Sciences, pages 63-258 (the entire disclosure of which isherein incorporated by reference) can be used. Suitable flavorantsinclude wintergreen, peppermint, spearmint, menthol, fruit flavors,vanilla, cinnamon, spices, flavor oils and oleoresins, as known in theart. The amount of flavorant employed is normally a matter ofpreference, subject to such factors as flavor type, individual flavor,and strength desired. Preferably, the backing layer comprises from about0.1% to about 5% flavorant.

Sweeteners useful in the present invention include sucrose, fructose,aspartame, xylitol and saccharine. The choice of sweeteners and thedesired “sweetness” dictates the amount of sweetener to be added to thebacking layer. Preferably, the backing layer comprises sweeteners in anamount from about 0.001% to about 5.0%.

The non-woven binding material preferably comprises a spun bondedpolypropylene. The material and structure of the first part and thesecond part are preferably the same. The primary basis for thedistinction between the first part and the second part is the layer intowhich the individual layer is invested. The first part of the bindingmaterial is substantially invested in the oral care layer. The secondpart of the binding material is substantially invested in the backinglayer. Preferably, the first part of the binding material comprisesabout one half of the binding material and the second part of thebinding material comprises about one half of the binding material. Thus,about one half of the binding material is invested in the oral carelayer and about one half of the binding material is invested in thebacking layer.

Preferably, the face of the backing layer contacting the bindingmaterial is softened by heating prior to being invested by the bindingmaterial.

In one embodiment, the second part of the binding material isco-extensive with the backing layer. As used herein, “coextensive” meanshaving substantially the same length and width as the backing layer. Inother embodiments, the binding material is of smaller dimensions (i.e.,in length and/or width) than the backing layer, so that the materialcomprising the backing layer extends beyond one or more edges of thebinding material when the binding material is invested in the backinglayer.

The binding material preferably has minimal flexural stiffness; that is,the binding material does not resist deformation when the device ispressed into place on the teeth of the user. Thus, the binding materialcan be any thickness which does not interfere with the permanentdeformation of the device when pressure is applied by the user.Preferably, the binding material is from about 0.089 mm (3.5 mils) toabout 0.279 mm (11 mils) thick, more preferably about 0.114 mm (4.5mils) to about 0.203 mm (8 mils) thick, and particularly preferable atabout 0.152 mm (6 mils) thick. Proper binding material thickness isessential in ensuring that the oral care layer does not shrink away fromthe binding layer, resulting in the oral care layer delaminating fromthe backing layer.

The binding material can be any non-woven material. Non-woven materialsare a category of materials made primarily of textile fibers that arenot processed on conventional spindles, looms, or knitting machines, butrather the fibers are held together by bonding, fusing, or otherchemical, thermal or mechanical means. For example, structurally, thenon-woven material can be a felt, or chemically, it can be from thegroup consisting of a polyolefin (e.g. polyethylene and polypropylene),polyester, polyurethane, polyamide, polyaramide and glass. Preferably,the binding material comprises a spun bonded non-woven (i.e., anon-woven fabric formed by filaments that have been extruded, drawn,then laid on a continuous belt). More preferably, the binding materialcomprises a spun bonded polypropylene, for example Typar® or Remay®.However, the binding material can also be spun-laced (non-woven fabricproduced by entangling of fibers in a repeating pattern to form a strongfabric that is free of binders), carded (non-woven fabric produced by aprocess similar to carding wool in textile industry), “hook” or “loop”fabrics used in hook and loop fasteners, or other known variations.

The binding material can also comprise a color or pigment, which impartsa color or hue to the binding material. In embodiments where the backinglayer is uncolored but the binding material is colored, the color of thebinding material is preferably visible, thus making the device obtrusivewhen worn. The binding material can comprise the same colorizingcompounds in the same preferred concentrations listed above for coloringthe backing layer.

The oral care layer comprises at least one oral care agent and at leastone hydrophilic polymer. A portion of the oral care layer issubstantially invested by a first part of the non-woven bindingmaterial. The oral care layer is generally co-extensive with the bindingmaterial.

The oral care layer has minimal flexural stiffness; that is, the oralcare layer does not resist deformation when the device is pressed intoplace on the teeth of the user. Thus, the oral care layer can be anythickness which does not interfere with the permanent deformation of thedevice when pressure is applied by the user, and which allows a suitableamount of oral care agent to be contained within the layer for deliveryto the teeth. Preferably, the oral care layer is from about 0.025 mm toabout 4 mm thick, more preferably about from about 0.125 mm to about 1.5mm thick, particularly preferably from about 0.25 mm to 1.0 mm, forexample, about 0.3 mm thick.

A portion of the oral care layer is invested by the first part of thebinding material, meaning that more than an appreciable amount of theoral care layer penetrates below the surface of the first part of thebinding material to form a oral care layer/binding material composition.The portion of the oral care layer that is not invested by the bindingmaterial is located immediately adjacent to the oral care layer/bindingmaterial composition.

The oral care layer has an adhesiveness when hydrated that is sufficientto adhere the surface of the teeth and surrounding soft tissue when thedevice is conformed to the teeth and dental arch. The oral care layershould adhere to the teeth and surrounding soft tissue for as long aperiod of time as necessary for the oral care agent to be delivered andeffect the desired result. Typically, the device is left on the teethfor approximately 15 minutes to one hour, although shorter or longertimes are contemplated. Methods for delivering an oral care agent to theteeth with the present device are described in more detail below.

The oral care layer also has sufficient adhesiveness and cohesiveness tothe teeth so that the device is resistant to inadvertent removal and yetis easily removed from the teeth. The substantial investment of thebinding material in the oral care layer causes a bond between thebinding material and the oral care layer that is greater than thestrength of the adhesive bond between the oral care layer and the teeth.Moreover, the substantial investment of the binding material in both theoral care layer and the backing layer prevents the device fromdelaminating upon removal from the teeth.

The adhesive properties of the oral care layer should not be weakened ordestroyed by exposure to moisture or high humidity. In one embodiment,the adhesive properties of the oral care layer with respect to bondingto the teeth are enhanced by hydration, for example with water orsaliva.

As used herein, “adhesion” or “adhesiveness” refers to the molecularattraction exerted between surfaces of bodies in contact. As usedherein, “cohesion” or “cohesiveness” refers to the molecular attractionby which the particles of a body are united throughout the mass.

Adhesiveness can be expressed in units of force per distance (e.g.,“Newtons/meter” or “N/m”), and cohesiveness can be expressed in terms oftack. A suitable strength for an adhesive bond between the oral carelayer and the surface of the teeth ranges from about 200 to about 400N/m. A suitable tack for the oral care layer is greater than about 50g/cm².

Adhesiveness and tack can be measured by standard tests such as 90 or180 degree peel force tests, rolling ball-style tests, tack tests (e.g.,the PKI or TRBT tack determination methods), and static shear tests, andother tests such as are known in the art.

For example, a modified commercially available surface tensiometersuitable for measuring the adhesive strength of bioadhesives isdescribed in U.S. Pat. No. 4,615,697 of Robinson, the entire disclosureof which is herein incorporated by reference. The adhesiveness and tackof the present oral care layer can also be determined using a TA.XT2Texture Analyzer (Texture Technologies Corp.) together with an XT.RADimension software package (Stable Micro Systems, Ltd.), according tothe manufacturer's instructions.

According to the operation of a TA.XT2 texture analyzer, the device fortesting is mounted on a block with the oral care layer exposed, and aprobe attached to the TA.XT2 texture analyzer is moved at a fixed speedagainst the adhesive surface of the oral care layer, distorting the oralcare layer to a fixed penetration depth. The probe is permitted to dwellat the penetration depth for a fixed time. The probe is then withdrawnfrom the oral care layer at a fixed speed, and the peak force requiredto detach the probe from the oral care layer surface is measured.Suitable conditions for measuring the adhesiveness and tack of thepresent oral care layer with the TA.XT2 Texture Analyzer are a probediameter of 0.80 cm, a penetration depth of 0.1 mm, a penetration rateof 1.0 mm/sec, a dwell time of 10 sec, and a withdrawal rate of 5.0mm/sec.

In some embodiments, the oral care agent is entrapped within the oralcare layer by a matrix formed by the hydrophilic polymer. The oral careagent is released from the hydrophilic polymer matrix upon hydration andswelling of the hydrophilic polymer, whereupon the agent is delivered tothe teeth to produce the desired effect.

Preferably, prior to release and/or activation with water or saliva, theoral care agent within the oral care layer is stable such that minimalpotency is lost during normal storage conditions (i.e., in a vacuumsealed package at ambient temperature and humidity) for greater than oneyear prior to use.

Preferably, the oral care layer comprises a pressure-sensitive adhesivecomprising an oral care agent and a hydrophilic polymer that is madetacky (i.e., it is rendered pressure-sensitive) at room temperature byaddition of a water-soluble plasticizer that is miscible with thepolymer.

Hydrophilic polymers useful in the oral care layer are characterized asbeing solid at room temperature; that is, as having a glass transitiontemperature T(g), or melting point T(m), higher than about 25° C. andlower than about 120° C., and more preferably higher than about 30° C.,and lower than about 100° C. The hydrophilic polymers also preferablyhave a hydrophilicity as measured by water uptake greater than about25%. Suitable polymers include polysaccharides (e.g., starches andstarch derivatives, cellulose-derivatives such as sodium carboxymethylcellulose or “Na—CMC”), and water-soluble synthetic polymers (e.g.,2-acrylamido-2-methyl-propanesulfonic acid or “poly AMPS”, polyvinylpyrrolidone or “PVP,” polyvinyl alcohol or “PVA,” hydroxypropylcellulose or “HPC”, polyethylene oxide or“PEO”, polyacrylic acid or“PAA,” and carboxylic acid polymers such as the Carbopols and Carbomersavailable from B. F. Goodrich); polypeptides; and natural gums such asxanthan gum, karaya gum, and gelatin.

Plasticizers useful in the oral care layer are characterized as beingliquid at room temperature and having a boiling point higher than about80° C. Suitable plasticizers include glycerin, sorbitol, any of theglycols, polysorbate 80, triethyl titrate, acetyl triethyl titrate, andtributyl titrate.

Preferably, the hydrophilic polymer comprising the oral care layercomprises crosslinked or non-crosslinked polymers such as2-acrylamido-2-methyl-propanesulfonic acid (poly AMPS); polyvinylpyrrolidone (PVP); polyethylene oxide (PEO); polyacrylates (e.g., theEudragits™, available from Rohm America, Inc., Piscataway, N.J.);polyvinyl alcohol (PVA); carboxylic acid polymers (e.g., Carbopols™ andCarbomers™ available from B. F. Goodrich). The Eudragits™ arecharacterized as one of (1) an anionic copolymer based on methacrylicacid and methylmethacrylate wherein the ratio of free carboxyl groups tothe ester groups is approximately 1:1, (2) an anionic copolymer based onmethacrylic acid and methylmethacrylate wherein the ratio of freecarboxyl groups to the ester groups is approximately 1:2, (3) acopolymer based on acrylic and methacrylic acid esters with a lowcontent of quaternary ammonium groups wherein the molar ratio of theammonium groups to the remaining neutral methacrylic acid esters is1:20, or (4) a copolymer based on acrylic and methacrylic acid esterswith a low content of quaternary ammonium groups wherein the molar ratioof the ammonium groups to the remaining neutral methacrylic acid estersis 1:40.

Particularly preferred are oral care layers comprising thepoly(AMPS)-based pressure sensitive adhesives described in U.S. Pat. No.4,581,821 of Cahalan et al., or comprising the PEG-PVP-based pressuresensitive adhesives described in U.S. Pat. No. 6,576,712 of Feldstein etal, the entire disclosures of which are herein incorporated byreference.

The oral care layer can also comprise a scrim, which serves to furtherreinforce the oral care layer against fragmentation and delamination.Preferably, the scrim is embedded in the portion of the oral care layerthat is not occupied by the first part of the binding material. Thescrim can comprise a variety of woven or non-woven materials orperforated sheetlike materials which are known in the art. Suitablewoven materials for forming the scrim include cloth or gauze formed ofnatural or synthetic fibers such as cotton; polyester (e.g., DACRON®fibers, and SONTARA® fabrics such as polyester grades 8000, 8027 and8100, E. I. dupont de Nemours & Co.); polyolefins (e.g., polyethylene,polypropylene and the like); polyurethane; polyamide (e.g., NYLON®fiber); polyaramide (e.g., KEVLAR® fiber); and glass (e.g., FIBERGLAS™fiber). The woven materials for forming the scrim can be a conventionalweave or a nonconventional weave such as either of the “hook” or “loop”fabrics used in hook and loop fasteners.

Suitable non-woven materials for forming the scrim include felt andsynthetic fibers such as polyester; polyolefins (e.g., polyethylene,polypropylene and the like); polyurethane; polyamide (e.g., NYLON®fiber); polyaramide (e.g., KEVLAR® fiber); and glass (e.g., FIBERGLAS™fiber). Particularly preferred is a non-woven polyolefin fabric, such asDELNET® fabric from DelStar Technologies, Inc. (Middletown, Del.).

Suitable perforated sheetlike materials for forming the scrim includefine pitch polypropylene net.

Preferably, the scrim should be free of objectionable taste or odor, andbe safe for use in the mouth. The material forming the scrim alsopreferably has a melting temperature above the melting or softeningtemperature of the material forming the oral care layer.

In an embodiment, the scrim is embedded in the oral care layer. Thescrim can be embedded in the oral care layer by techniques well-known inthe art. For example, the scrim can be sandwiched between layerscomprised of the materials that make up the oral care layer. The oralcare layer can also be extruded directly onto the scrim, whereupon themelted material comprising the oral care layer flows through and aroundthe openings in the scrim material. Upon cooling of the melted oral carelayer material, the scrim is entirely surrounded by the oral care layer.Other methods for embedding a non-woven, woven or perforated sheet scrimin the oral care layer will be apparent to those of ordinary skill inthe art.

In one embodiment, the material comprising the oral care layer releasesthe oral care agent over time, so that activated oral care agent isdelivered to the teeth throughout the entire period during which thedevice is used. Such oral care layers are called “sustained-release”oral care layers. In one embodiment, oral care agent is delivered to theteeth in a substantially uniform quantity per unit time by thesustained-release oral care layer. In another embodiment, an oral careagent is delivered in non-uniform quantities per unit time. For example,larger quantities of activated oral care agent can be delivered in agiven portion of the treatment period as compared to the other portions;e.g., more oral care agent can be delivered during the first quarter,third or half of the treatment period than in the remaining portions ofthe treatment period.

The sustained-release oral care layer delivers the oral care agent bydiffusion of the oral care agent through the oral care layer toward thesurface of the teeth and surrounding tissue. Diffusion outward into theoral cavity is blocked by the backing layer, which is substantiallyimpermeable to the oral care agent and to saliva under the conditions inwhich the device is used. A limited amount of oral care agent may escapeinto the oral cavity by diffusion outward from the edges of the deviceduring use; however, this should have a negligible impact on the safetyand efficacy of the device. It is preferred that the oral care layer isnot substantially degradable or erodable, so that little to nodegradation by-products are produced and released into the oral cavityduring use of the device.

The rate of delivery of the oral care agent from the oral care layer tothe teeth can be controlled by adjusting the concentration ofhydrophilic polymer and plasticizer in the oral care layer. Generally, ahigher concentration of hydrophilic polymer in the oral care layerresults in a higher cohesive strength of the layer, which in turn lowersthe rate of release of the oral care agent. The cohesiveness ofhydrophilic polymer-based materials suitable for use in the oral carelayer can be adjusted to a desired value according to principleswell-known in the art; see, for example, U.S. Pat. No. 4,581,821 ofCahalan et al., supra, and U.S. Pat. No. 6,576,712 of Feldstein et al.,supra.

The concentration of oral care agent in the oral care layer required todeliver the desired amount of oral care agent to the teeth andsurrounding tissue can vary depending on factors such as the type,length and frequency of treatment to be performed, the severity of thecondition, the age and health of the user, and the like. One of ordinaryskill in the art can readily vary the concentration of the oral careagent in the oral care layer in order to achieve a desired result.Generally, the amount of oral care agent in the oral care layer ispreferably from about 0.01% to about 40%, more preferably from about0.1% to about 20%, most preferably from about 0.5% to about 14%, andparticularly preferably from about 1% to about 10%. Preferred amounts ofa given oral care agent to be included in the oral care layer areprovided below.

The oral care agent can be any pharmaceutically active agent useful intreating physiological conditions involving the teeth and surroundingtissue. As used herein, a “pharmaceutically active agent” is anysubstance that can be released from the oral care layer to treat anundesirable physiological condition. Undesirable, physiologicalconditions involving the teeth or surrounding tissue which are amenableto treatment with the present device include: halitosis; periodontal andoral infections; periodontal lesions; dental caries or decay;gingivitis; and other periodontal diseases.

The pharmaceutically active oral care agent can be, for example,non-steroidal anti-inflammatories/analgesics (preferably 0.1-5% in theoral care layer); steroidal anti-inflammatory agents (preferably0.002-0.5% in the oral care layer); local anesthetics (preferably0.05-2% in the oral care layer); bactericides/disinfectants (preferably0.01-10% in the oral care layer); antibiotics (preferably 0.001-10% inthe oral care layer); antifungals (preferably 0.1-10% in the oral carelayer); tooth desensitizing agents (preferably 0.1-10% in the oral carelayer); fluoride anticavity/antidecay agents (preferably 50 ppm to10,000 ppm in the oral care layer); anti-tartar/anti-calculus agents;enzymes which inhibit the formation of plaque, calculus or dentalcaries; and nutritional supplements for local delivery to the teeth andsurrounding tissue.

Suitable non-steroidal anti-inflammatory/analgesic agents includeacetaminophen; methyl salicylate; monoglycol salicylate; aspirin;mefenamic acid; flufenamic acid; indomethacin; diclofenac; alclofenac;diclofenac sodium; ibuprofen; flurbiprofen; fentizac; bufexamac;piroxicam; phenylbutazone; oxyphenbutazone; clofezone; pentazocine;mepirizole; and tiaramide hydrochloride.

Suitable steroidal anti-inflammatory agents include hydrocortisone;prednisolone; dexamethasone; triamcinolone acetonide; fluocinoloneacetonide; hydrocortisone acetate; prednisolone acetate;methylprednisolone; dexamethasone acetate; betamethasone; betamethasonevalerate; flumetasone; flourometholone; budesonide; and beclomethasonedipropionate.

Suitable local anesthetics include dibucaine hydrochloride; dibucaine;lidocaine hydrochloride; lidocaine; benzocaine; p-buthylaminobenzoicacid 2-(diethylamino)ethyl ester hydrochloride; procaine hydrochloride;tetracaine hydrochloride; chloroprocaine hydrochloride; oxyprocainehydrochloride; mepivacaine; cocaine hydrochloride; and piperocainehydrochloride.

Suitable bactericides/disinfectants include thimerosol; phenol; thymol;benzalkonium chloride; benzethonium chloride; chlorhexidine; providoneiodide; cetylpyridinium chloride; eugenol, and trimethylammoniumbromide.

Suitable antibiotics include penicillin; meticillin; oxacillin;cefalotin; cefaloridin; erythromycin; lincomycin; tetracycline;chlortetracycline; oxytetracycline; metacycline; chloramphenicol;kanamycin; streptomycin; gentamicin; bacitracin; and cycloserine.

Suitable antifungal drugs include amphotericin; clotrimazole; econazolenitrate; fluconazole; griseofulvin; itraconazole; ketoconazole;miconazole; nystatin; terbinafine hydrochloride; undecenoic acid; andzinc undecenoate.

Suitable tooth-desensitizing agents include potassium nitrate andstrontium chloride.

Suitable fluoride anticavity/antidecay agents include sodium fluoride,potassium fluoride and ammonium fluoride.

Suitable anti-tartar/anti-calculus agents include phosphates such aspyrophosphates, polyphosphates, polyphosphonates (e.g.,ethane-1-hydroxy-1,1-diphosphonate, 1-azacycloheptane-1,1-diphosphonate,and linear alkyl diphosphonates), and salts thereof; linear carboxylicacids; and sodium zinc citrate; and mixtures thereof. Preferredpyrophosphate salts are the dialkali metal pyrophosphate salts,tetra-alkali metal pyrophosphate salts; and the hydrated or unhydratedforms of disodium dihydrogen pyrophosphate (Na₂H₂P₂O₇), tetrasodiumpyrophosphate (Na₄P₂O₇), and tetrapotassium pyrophosphate (K₄P₂O₇). Thepyrophosphate salts are described in more detail in Kirk & Othmer,Encyclopedia of Clinical Technology Third Edition, Volume 17,Wiley-Interscience Publishers (1982), the entire disclosure of which isherein incorporated by reference in its entirety.

Suitable enzymes that inhibit the formation of plaque, calculus ordental caries include: proteases that break down salivary proteins whichare absorbed onto the tooth surface and form the pellicle, or firstlayer of plaque; lipases that destroy bacteria by lysing proteins andlipids that form the structural component of bacterial cell walls andmembranes; dextranases, glucanohydrolases, endoglycosidases, andmucinases that break down the bacterial skeletal structure that forms amatrix for bacterial adhesion to the tooth; and amylases that preventthe development of calculus by breaking-up the carbohydrate-proteincomplex that binds calcium. Preferred enzymes include any of thecommercially available proteases; dextranases; glucanohydrolases;endoglycosidases; amylases; mutanases; lipases; mucinases; andcompatible mixtures thereof.

Suitable nutritional supplements for local delivery to the teeth andsurrounding tissue include vitamins (e.g., vitamins C and D, thiamine,riboflavin, calcium pantothenate, niacin, folic acid, nicotinamide,pyridoxine, cyanocobalamin, para-aminobenzoic acid, and bioflavonoids);and minerals (e.g., calcium, phosphorus, fluoride, zinc, manganese, andpotassium); and mixtures thereof. Vitamins and minerals useful in thepresent invention are disclosed in Drug Facts and Comparisons (looseleaf drug information service), Wolters Kluer Company, St. Louis, Mo.,1997, pp 3-17; the entire disclosure of which is herein incorporated byreference.

The oral care agent can also be any cosmetically active agent. As usedherein, a “cosmetically active agent” includes any substance that can bereleased from the oral care layer to effect a desired change in theappearance of the teeth or surrounding tissue, or which imparts asocially desirable characteristic to the user, such as fresh breath. Forexample, a cosmetically active agent can be a breath freshener or anagent which effects whitening or bleaching of the teeth. Recognizingthat in some cultures or in certain segments of Western societycoloration of the teeth may be significant or desirable, thecosmetically active agent can also be any agent which imparts a color ortint to the teeth.

Suitable tooth whitening agents include peroxides, metal chlorites,perborates, percarbonates, peroxyacids, and combinations thereof.Suitable peroxide compounds include hydrogen peroxide, calcium peroxide,carbamide peroxide, and mixtures thereof. The preferred peroxides arehydrogen and carbamide peroxide. Suitable metal chlorites includecalcium chlorite, barium chlorite, magnesium chlorite, lithium chlorite,sodium chlorite, and potassium chlorite; hypochlorite and chlorinedioxide. The preferred chlorite is sodium chlorite.

The preferred concentration of tooth whitening agent in the oral carelayer of from about 0.01% to about 40%. If a peroxide compound is chosenas the tooth whitening agent, the peroxide compound should be equivalentto about 0.1% to about 20% of hydrogen peroxide, preferably from about0.5% to about 13% of hydrogen peroxide, and most preferably from about1% to about 10% of hydrogen peroxide, for example 9% of hydrogenperoxide.

As used herein, a “hydrogen peroxide equivalent” is the amount ofperoxide compound necessary to deliver the same amount of hydroxylradicals as a given. amount of hydrogen peroxide. For example, it takes3 moles of carbamide peroxide to deliver the same number of hydroxylradicals as 1 mole of hydrogen peroxide. Therefore, to deliver thehydrogen peroxide equivalents disclosed in the preceding paragraph,carbamide peroxide should generally be present in an amount of fromabout 0.3% to about 60% and preferably from about 1.5% to about 39%,particularly preferably from about 3% to about 30%, for example 27%, inthe oral care layer.

If hydrogen peroxide is used in the oral care layer, it is preferablyfrom about 0.1% to about 30% by weight of the oral care layer. Morepreferably the amount of hydrogen peroxide in the oral care layer isfrom about 3% to about 20%. Most preferably the amount of hydrogenperoxide in the oral care layer is from about 6% to about 12%.

The oral care layer can also comprise additional ingredients which donot alter the adhesive, cohesive or structural properties of the layer,or interfere with the delivery of the oral care agent. Such additionalingredients include coloring compounds as described above; foodadditives; flavorants; sweeteners; and preservatives.

Any natural or synthetic flavorant or food additive, such as thosedescribed in Chemicals Used in Food Processing, Pub. No. 1274, NationalAcademy of Sciences, pages 63-258 (the entire disclosure of which isherein incorporated by reference) can be used. Suitable flavorantsinclude wintergreen, peppermint, spearmint, menthol, fruit flavors,vanilla, cinnamon, spices, flavor oils and oleoresins, as known in theart. The amount of flavorant employed is normally a matter ofpreference, subject to such factors as flavor type, individual flavor,and strength desired. Preferably, the oral care layer comprises fromabout 0.1% to about 5% flavorant.

Sweeteners useful in the present invention include sucrose, fructose,aspartame, xylitol and saccharine. The choice of sweeteners and thedesired “sweetness” dictates the amount of sweetener to be added to theoral care layer. Preferably, the oral care layer comprises sweeteners inan amount from about 0.001% to about 5.0%.

The device of the invention is preferably substantially non-flat asprovided to the user. As used herein, “substantially non-flat” meansthat the device is bent, creased or curved along its long axis. Forexample, the device may have a “J”, “reversed J”, or “C” shape or thelike when viewed in cross-section. The oral care layer is located to theinside of the bend or curve (e.g., the concave side), so that the oralcare layer is protected from inadvertent contact by the user. In normaluse and handling, the user should only touch the backing layer, whichforms the outside of the device. In the preferred embodiment, a usersimple slides the substantially non-flat device onto the teeth andpresses the device onto the teeth so that the oral care layer contactsat least the front portion of the teeth.

In addition, the oral care layer can be protected with an optionalrelease liner, or a covering enclosing the inside (e.g., the concaveside) of device. The release liner may be formed from any material whichexhibits less affinity for the oral care substance than the oral caresubstance exhibits for itself and for the release liner material. Therelease liner preferably comprises a rigid sheet of material such aspolyethylene, paper, polyester, or other material which is then coatedwith a non-stick type material. The release liner material can be coatedwith wax, silicone, teflon, fluoropolymers, or other non-stick typematerials. A preferred release liner is Scotchpak(® produced by 3M. Therelease liner may be cut to substantially the same size and shape as theoral care layer surface of the device, or the release liner may be cutlarger than the oral care layer surface of the device to provide areadily accessible means for separating the material from the strip. Therelease liner may be formed from a brittle material which cracks whenthe device is flexed, from multiple pieces of material, or from a scoredpiece of material. Alternatively, the release liner can comprise twooverlapping pieces, such as a typical adhesive strip bandage design. Inone embodiment, the optional release liner can be integral with apackage enclosing the device. A further description of materialssuitable for use as a release liner is found in Kirk-Othmer Encyclopediaof Chemical Technology, Fourth Edition, Volume 21, pp. 207-218, theentire disclosure of which is incorporated herein by reference. Thecovering enclosing the inside (e.g., the concave side) of the presentdevice can be made of similar materials.

In addition to the curve, crease or bend which may be possessed by thedevice of the invention when viewed in cross section, the device is ofan overall size and shape to fit over some or all of the teeth in eitherthe upper or lower dental arch of the user's mouth. Although the presentdevice can be used on primary, mixed or permanent dentition, for ease ofreference the invention will be discussed in terms of the permanentdentition of an average adult human being.

An adult human user will typically have a permanent dentition composedof sixteen teeth in the upper dental arch, and sixteen teeth in thelower dental arch. As used herein, “dental arch” means an individual rowof teeth forming a tooth row attached to either the upper or lower jawbone. The curve of the dental arch is known as the catenary arch. Eachdental arch has the following tooth types arranged symmetrically in thearch: four incisors or front teeth, two canines, four bicuspids and sixmolars. The incisors and canines are called the anterior teeth, and thebicuspids and molars are called the posterior teeth. The shape of theanterior teeth is generally the same for the upper and lower dentalarch, with the top set generally being larger. The posterior teeth areof generally the same size and shape in both the upper and lower dentalarches.

Preferably, the device is of sufficient length to cover at least thefacial surface of the anterior teeth in a dental arch, and is ofsufficient width to extend from the facial surface of the teeth, overthe crowns, and at least partially cover the lingual surface of theteeth. Generally, the device will begin coverage of the facial surfaceof the teeth at the point where the facial surface contacts the gums. Itis understood that the device may partially cover the gums or othersurrounding tissue. As used herein, the “facial” surface of a tooth isthe surface toward the cheeks or lips, and the “lingual” surface of atooth is the surface toward the tongue.

In a more preferred embodiment, the device is of sufficient length andwidth to cover the facial surface, crowns and at least partially coverthe lingual surface of the anterior teeth in a dental arch. Particularlypreferred is a device having sufficient length and width to cover thefacial surface, crowns and at least partially cover the lingual surfaceof the anterior and at least a portion of the posterior teeth in adental arch.

For a device designed to fit the upper dental arch, a suitable length isfrom about 7 cm to about 9 cm, and a suitable average width is fromabout 0.8 cm to about 2.5 cm. For a device designed to fit the lowerdental arch, a suitable length is from about 4 cm to about 6 cm, and asuitable average width is from about 1 cm to about 2 cm. It isunderstood that the device is intended to fit a range of similarly-sizeddental arches, and that the device, as used, is conformed to fit thedental arch of a particular user. Therefore, the dimensions presentedherein are not intended to be limiting, but are rather presented as aguide for constructing the device. For example, devices designed for usein children or smaller adults are proportionally smaller than thosedescribed above for the normal-sized adult.

The device can be essentially any shape which allows sufficient coverageof the teeth, as discussed above. For example, when viewed in plan view,the device can be straight, or can be slightly bent; e.g., in conformitywith the catenary arch of the upper or lower human dental arch. Wherethe device is designed to fit over all the teeth in a dental arch, thedevice is preferably bent into a horseshoe-shape that generally matchesthe catenary arch.

In flattened form and viewed in plan view, the device can besubstantially rectangular in shape; e.g., having four edges which eachpair of non-intersecting edges are close to parallel or are arched inthe same way. For example, a device in which the “front” edge of thedevice and the “back” edge of the device are curved in the same way, andthe side edges are essentially parallel or slightly off-parallel, isconsidered to be rectangular in shape; see, e.g., FIG. 12. As usedherein, the “front” edge of the device is the long edge of that portionof the device placed against the facial surface of the teeth. As usedherein, the “back” edge of the device is the long edge of that portionof the device placed against the lingual surface of the teeth. The“side” edges are the remaining edges of the device. The front and backedges are non-intersecting, and the “side” edges of the device arenon-intersecting. The intersecting edges (e.g., a side edge and thefront edge) do not have to intersect at exactly a right angle to beconsidered rectangular. Rather, the corner angle can be approximately90°. Moreover, the corners formed by the intersecting edges can berounded and still considered rectangular.

The device can also be substantially trapezoidal in shape when inflattened form and viewed in plan view. As used herein, “trapezoidal inshape” means any shape having four edges where the front and back edgesare generally parallel or arched the same way, and the back edge isshorter than the front edge. The side edges are generally not parallel.For example, the device may be trapezoidal in shape when the front edgeis convex and the back edge is concave and is also shorter than thefront edge, and the side edges are not parallel; see, e.g., FIG. 13. Thetrapezoidal shape may help to reduce bunching or buckling of the devicewhen placed on the dental arch, and allow the oral care layer moreefficiently contact the surfaces of the teeth.

Alternatively, the shape of the device when in flattened form and viewedin plan view can be generally round, oval, or polygonal. It isunderstood that the shape of the device, when in flattened form andviewed in plan, does not have to be symmetrical. Moreover, the edges ofthe device need not be straight, but can be irregular.

Any or all of the edges of the device may be notched. By notched it ismeant that there are one or more recesses, indentations, or curves ofsome type cut out of the device edge. The notches help prevent bucklingof the device when the device is formed over the curve of the dentalarch, and may be advantageously placed in the back edge of the device.In a preferred embodiment, the back edge of the device contains aplurality of notches substantially evenly spaced along the back edge.

Certain embodiments of the device will now be illustrated with referenceto the figures, where like reference numbers indicated like structures.

FIGS. 1 and 2 show back isometric and front isometric views,respectively, of an oral care delivery device of the invention generallydesignated as 90, which is designed to fit the upper dental arch. Thedevice is bent into a horseshoe-shape that generally conforms to thecatenary arch of a user. The inside 100 of the device, which is boundedby front edge 110, back edge 120, left side edge 130 and right side edge140, contains the oral care layer.

FIG. 3 shows a top plan view of the device of FIGS. 1 and 2. Line 5-5 inFIG. 3 bisects the device along a line corresponding to the medial lineof a dental arch, and defines the two arms of the horseshoe. Thehorseshoe arms are set at angle α of approximately 36°, generallycorresponding to the angle of a user's teeth in the catenary arch. Mainfold line 150 and secondary fold lines 160 and 161 extend from left sideedge 130 to right side edge 140 along the long axis of the device.Generally, the fold lines are formed when the device is pressed orvacuum formed into a forming die during the folding process. Preferably,the fold lines correspond merely to the area of the device which isfolded, and not a structural characteristic that necessitates the fold.However, to necessitate the fold, the area of the dental waxcorresponding to the fold lines can be weakened, scored, etched, gouged,or impressed by stamping or other similar mechanical means.

The device is folded along the main and secondary fold lines, with theoral care layer to the inside 100 of the device, and the backing layerto the outside. The main fold line 150 and secondary fold lines 160 and161 are offset towards back edge 120 of the device. Folding of thedevice along the offset fold lines provides a portion of the inside ofthe device from the front edge to the fold lines which is larger thanthe portion of the device from the back edge to the fold lines. Thislarger portion is intended to contact the facial surface of the teethwhen the device is placed over the dental arch. As used herein, an“axis” of the device includes both linear and curvilinear lines runningfrom side edge to side edge of the device. FIG. 4 is a back view of thedevice of FIGS. 1 and 2, showing how folding of the device along theoffset main fold line 150 and secondary fold lines 160 and 161 dividesthe device into larger and smaller portions as described above.

FIG. 5 is a cross-sectional view of the device 90 of FIGS. 1 and 2 alongline 5-5 of FIG. 3, showing the arrangement of the oral care layer 190,the first part of the non-woven binding material 180 substantiallyinvested in the oral care layer 190, the second part of the non-wovenbinding material 182 substantially invested in the backing layer 170,and the backing layer 170. The device is bent along main fold line 150and secondary fold lines 160 and 161 into a “reversed J” shape, so thatthe oral care layer 190 is located to the inside 100 of the device. Thelong arm of the “reversed J” ends in the front edge 110.

FIG. 5A is a blow-up of a portion of the cross-section view of FIG. 5,further illustrating the arrangement of the oral care layer 190, thefirst part of the non-woven binding material 180 substantially investedin the oral care layer 190, the second part of the non-woven bindingmaterial 182 substantially invested in the backing layer 170, and thebacking layer 170.

FIG. 6 is a top plan view of the device of FIGS. 1 and 2 shown inflattened form to illustrate the rectangular shape of the unfoldeddevice. Front edge 110 and back edge 120 are non-intersecting, and leftside edge 130 and right side edge 140 are non-intersecting. Main foldline 150 and secondary fold lines 160 and 161 are located approximately⅓ the distance from front edge 110 to back edge 120.

FIG. 7 is a back isometric view of another oral care delivery device ofthe invention generally designated 190, which is designed for placementover either the upper or lower dental arch. The inside 200 of thedevice, which is bounded by front edge 210, back edge 220, left sideedge 230 and right side edge 240, contains the oral care layer. Aplurality of notches 245 are spaced essentially evenly along the backedge 210 of the device. As described above, the notches help preventbuckling of the device when the device is manipulated to conform to thecurve of the dental arch. The device is substantially straight, and ismolded to fit the curvature of the catenary arch during placement in theuser's mouth.

FIG. 8 shows the device 190 of FIG. 7 in flattened form to illustratethe rectangular shape of the unfolded device, and the positioning ofnotches 245. The device has a main fold line 250 and secondary foldlines 260 and 261 offset from front edge 210 as in the previousembodiment, located approximately ⅓ the distance from front edge 210 toback edge 220. The notches 245 extend from back edge 210 to thesecondary fold 230 line closest to the back edge, with the apex of thenotches contacting the secondary fold line. The sides of each notch forman angle β of approximately 28°.

FIG. 9 is a back view of the device 190 of FIG. 7, showing how foldingof the device along the offset main fold line 250 and secondary foldlines 260 and 261 provides a portion of the device from the front edgeto the fold lines which is larger than the portion from the back edge tothe fold lines. The larger portion contacts with the facial surface ofthe teeth when the device is placed over the dental arch. The notches245 are contained within the portion of the device which contacts thelingual surface of the teeth when placed over the dental arch. The sidesof each notch form an angle γ of approximately 28°.

FIG. 10 is a cross-sectional view of the device 190 of FIG. 7 takenalong line 10-10 of FIG. 9, showing the arrangement of an oral carelayer 290, a first part of the non-woven binding material 280substantially invested in the oral care layer 290, a second part of thenon-woven binding material 282 substantially invested in a backing layer270, and the backing layer 270. The device is bent along main fold line250 and secondary fold lines 260 and 261 into a “reversed J” shape, sothat the oral care layer 290 is located to the inside 200 of the device.The long arm of the “reversed J” ends in the front edge 210. The surfaceof oral care layer 290 between the secondary fold lines 260 and 261 isbent into an angle δ of approximately 90° by folding the device alongthe main fold line 250. The surface of the oral care layer 290 betweenfront edge 210 and the secondary fold line 260, and the surface of theoral care layer 290 between the back edge 220 and the secondary foldline 261, are bent into an angle ε of approximately 45° relative to eachother by folding the device along each secondary fold line.

FIG. 11 is a top plan view of a further oral care delivery device of theinvention generally designated 290, which is designed to fit the upperdental arch of a user. The device is shown in flattened form toillustrate the rectangular shape. The rectangle is defined by front edge310 and back edge 320, and side edges 330 and 340. The device has asingle fold line 350 which is slightly offset from the center axis ofthe device toward the back edge 320. A plurality of substantially evenlyspaced notches 345 are cut into back edge 320. The sides of each notch345 form an angle ζ of approximately 22°, and the apex of each notchcontacts fold line 350.

FIG. 12 is a top plan view of another oral care delivery device of theinvention generally designated 390, which is designed to fit the upperdental arch of a user. The device is shown in flattened form toillustrate the rectangular shape. The rectangle is defined by front edge410 and back edge 420, and side edges 430 and 440. Front edge 410 andback edge 420 are curved in the same way and side edges 430 and 440 areslightly off-parallel. The device has a single fold line 450 which isslightly offset from the center axis of the device toward the back edge.A plurality of substantially evenly spaced notches 445 are cut into backedge 420. The sides of each notch 445 form an angle η of approximately22°, and the apex of each notch contacts fold line 450.

FIG. 13 is a top plan view of a further oral care delivery device of theinvention generally designated 490, which is designed to fit the lowerdental arch of a user. The device is shown in flattened form toillustrate the essentially trapezoidal shape. The trapezoid is definedby front edge 510 and back edge 520, and side edges 530 and 540. Frontedge 510 and back edge 520 are slightly curved, and back edge 520 isshorter in length than front edge 510. Side edges 530 and 540 are notstraight, but follow an irregular course which forms protrusions oneither side of the flattened pattern. When the device is folded andplaced over the dental arch, the protrusions ensure that at least thefacial surface of the incisors are in contact with the oral care layer.The device has a single fold line 550 which is slightly offset from thecenter of the device toward the back edge 520. A plurality ofsubstantially evenly spaced notches 545 are cut into back edge 520. Thesides of each notch 545 form an angle θ of approximately 220, and theapex of each notch contacts fold line 550.

The device can be constructed using techniques well known in the art.For example, the components comprising the backing layer can be mixed,melted and extruded in a continuous or discontinuous layer of a desiredthickness, which can be cut to the appropriate size and shape.Alternatively, the backing layer can be produced by pressing the mixed,melted components into a flat sheet of a desired thickness, which isthen cut to the appropriate size and shape. The binding material can beinvested in the backing layer by techniques well known in the art, suchas lamination, hot-melt extrusion, and the like, or the two layers canbe coextruded.

Likewise, the oral care layer can be prepared using polymer synthesisand formulation techniques known in the art (see, e.g., U.S. Pat. No.4,581,821 of Cahalan et al., supra, and U.S. Pat. No. 6,576,712 ofFeldstein et al., supra), and formed into a layer of a desired thicknesssuitable for investment by a first part of the binding material. Forexample, the polymers, plasticizers oral care agent and any othercomponents comprising the oral care layer can be melted in a hotmeltmixer and extruded as a sheet between two release liners, or can becasted. The oral care layer can be removed from between the releaseliners and integrated with the binding material; e.g., by lamination.Alternatively, the oral care layer can be extruded directly onto thebinding material.

In one embodiment, an oral care agent, for example a hydrogen orcarbamide peroxide, can be placed (e.g., by printing) on top of a firstpart of the non-woven binding material, the second part of which hasbeen substantially invested into a backing layer. A melted mixturecomprising all the components of an oral care layer except the oral careagent is then extruded directly on top of the oral care agent. Thecomponents of the oral care layer flow into and around the openings inthe binding material such that the pore space of the binding material isfully encompassed by the oral care agent and such that the oral careagent contacts the backing layer. As the melted oral care layercomponents solidify, the oral care agent is drawn into and distributedthroughout the oral care layer.

Optionally, a scrim can be placed over the oral care agent which hasbeen placed on top of the binding material, prior to extrusion of theoral care layer. The melted mixture comprising the remaining oral carelayer components is then extruded onto the scrim, where it flows intoand around the openings in the scrim so that the scrim is entirelysurrounded by the melted oral care layer material. As the oral carelayer solidifies, it absorbs the oral care agent as described above, andalso entraps the scrim so that the scrim is embedded in the oral carelayer.

Specific processes for constructing the devices of the invention aregiven in the Examples below.

Preferably, the device of the invention is provided to the usersubstantially ready for placement on the teeth. That is, the device willpreferably be provided in substantially non-flat form, and all the userneed do is conform the device onto the upper or lower dental arch withnormal manual pressure.

In practice, the user wets the device before placement in the mouth,e.g., with water or saliva. Alternatively, the user can wet the surfaceof the teeth to be treated; e.g., with water or saliva, before placementof the device in the mouth. Wetting the device causes the hydrophilicpolymer in the oral care layer to begin to swell, which in turn mayenhance the adhesive properties of the layer and/or activate the oralcare agent. Swelling of the hydrophilic polymer can also cause the oralcare layer to fill in the cracks or irregularities found in the surfaceof the teeth and surrounding tissue, so that maximum contact is madewith these surfaces.

The device is then placed over the teeth to be treated, and formedaround the teeth and surrounding tissue with manual pressure. The deviceshould be conformed to the teeth so that the oral care layer issubstantially entirely in contact with at least the facial surfaces andthe crowns of the teeth to be treated. Depending on the size of thatportion of the device in contact with the lingual surface of the teethto be treated, the lingual surface of the teeth may only be partiallycovered.

Once formed around the teeth and surrounding tissue, the device is leftin place for a sufficient time to produce the desired effect. The lengthof time that the device should be left in place varies with the type oftreatment to be performed, the severity of the condition, the age andhealth of the user, and the like. The length of time which the device isleft on the teeth can therefore be varied in order to achieve a desiredresult. For both therapeutic and cosmetic applications, the device canbe left in place, for example, for about 15 minutes to about 4 hours pertreatment, preferably for about 30 minutes to about 1 hour pertreatment. Longer and shorter treatment times are contemplated.

For embodiments of the invention which employ an oral care layer capableof sustained release of the oral care agent, treatment times can besubstantially less than treatment times normally recommended for priordelivery systems. For example, treatment times of about 15 to about 30minutes with a device of the invention employing a sustained releaselayer can produce results comparable to or better than those achievedwith prior delivery systems using longer treatment times. Once a singletreatment has been completed, the device is simply removed from theteeth by the user and discarded.

The frequency and total number of therapeutic or cosmetic treatmentsalso depend on factors such as the type of treatment to be performed,the severity of the condition, the age and health of the user, and thelike. The frequency and total number of treatments with the presentdevice can therefore be varied in order to achieve a desired result. Fortherapeutic and cosmetic applications, the device can be applied to theteeth once or twice a day for 1 to 28 days, with the treatment regimenbeing repeated in 4 to 6 months from the last treatment. The preferredregimen is once a day for 3 days or 5 days.

For embodiments of the invention which employ an oral care layer capableof sustained release of the oral care agent, the frequency and totalnumber of treatments can be substantially less than those recommendedfor prior delivery systems. For example, a device employing a sustainedrelease oral care layer can be used once a day for 4 days to 2 weeks,with results comparable to or better than those achieved with priordelivery systems.

A preferred use of the device of the invention is to deliver a toothwhitening agent to the teeth. In practice, a device comprising an oralcare layer which comprises a tooth whitening agent is provided to theuse and is used as described above. Preferably, wetting the deviceactivates the tooth whitening agent.

The device is left in place for a sufficient time to produce the desiredeffect. The length of time that the device should be left in placevaries with the extent of the tooth discoloration or staining, thedegree of whitening desired by the user, and the like. The length oftime which the device is left on the teeth can therefore be varied inorder to achieve a desired result. Generally, the device can be left inplace for about 15 minutes to about 2 hours per treatment, preferablyfor about 30 minutes to about 1 hour per treatment. Longer and shortertreatment times are contemplated. A preferred treatment time isapproximately 1 hour.

In a preferred embodiment, the device comprises an oral care layercapable of sustained release of the tooth whitening agent. Inparticular, the oral care layer can comprise a PEG-PVP-based pressuresensitive adhesive as disclosed in U.S. Pat. No. 6,576,712 of Feldsteinet al, supra. Use of sustained-release oral care layers cansignificantly reduce treatment times as compared to the treatment timesnormally recommended for prior tooth whitening systems.

After a single treatment has been completed, the device is removed fromthe teeth by the user and discarded. The treatment is preferablyrepeated once a day (using a fresh device for each treatment) for one totwo weeks. More preferably, the tooth whitening treatment is repeatedonce a day for 4 to 7 days. The tooth whitening treatment regimen can berepeated after, for example, 4 to 6 months, depending on the extent towhich tooth discoloration or staining occurs during this period.

The device of the invention can be packaged by any means suitable forcontaining and transporting the devices to the consumer. Preferably, thedevice is placed in a hermetically sealed, single use pouch. Preferably,these pouches are made of silicone or fluorocarbon coated foil, Mylar,or wax coated foil to protect the device. The device can be sealedwithin the pouch under full or partial vacuum. A preferred pouch designis of the “peel-n-seal” type, wherein the user is presented with thedevice upon opening the pouch. The user may then grasp the device onlyby the backing layer, thus minimizing the chance of damaging orcontaminating the oral care layer.

It is contemplated that a plurality of devices in single use packagescan be packaged together. For example, a number of devices in single usepackages equal to the recommended number of treatments for a giventreatment regimen can be provided to the consumer in a larger package.

The invention will now be illustrated with the following non-limitingexample.

EXAMPLE 1 Construction of a Device for Delivering a Tooth WhiteningAgent

A delivery system for delivering a tooth whitening agent according tothe present invention was constructed as follows. TABLE 3 Backing LayerFormulation Item Brand Name Supplier Percentage MicrocrystallineMicrocrystalline Koster Keunen 50% Wax 180/185 Inc. Paraffin WaxParaffin 140/145 Koster Keunen 15% Inc. Hydrocarbon Escorez 5380ExxonMobil 35% Resin Chemical

The backing layer was prepared as follows. The microcrystalline wax,paraffin, and Escorez 5380 were weighed and transferred into a Qorpak®jar (Qorpak, Bridgeville, Pa.). The materials were heated to 85° C.-90°C. with stirring to obtain a clear liquid melt. The clear liquid meltwas cooled to 65° C.-75° C. with stirring. At this temperature, theviscosity of the clear liquid melt was such that a Gardner's knife wasused to make “draw-downs.” A silicone-coated PET release liner (Rexam92A; Rexam Coated Films & Papers, Charlotte, N.C.) was placed on a glassplate which had been heated to 38° C.-40° C. The clear liquid melt (at65° C.-75° C.) was coated onto the release liner at a thickness of about0.64 mm (25 mils) using a Gardner's knife. Immediately after drawingdown the clear liquid melt onto the release liner, the release linerwith the clear liquid melt was removed from the warm glass plate and wascooled to room-temperature. The clear liquid melt was solidified to formthe backing layer. The target thickness for the backing layer was about0.38 mm (15±2 mils). It is contemplated that this process could alsoproduce backing layers having a thickness of from about 0.025 mm (1 mil)to about 0.508 mm (20 mils).

Non-woven binding material—The binding material was composed of a layerof spun bonded polypropylene (Typar®). The target thickness of thebinding layer was about 0.152 mm (6 mils±1 mil). The binding materialwas invested in the backing layer as follows. The solidified backinglayer on the release liner produced above was placed, release liner-sidedown, on a glass plate and heated to 65°-70° C. The binding material wasplaced on the backing layer, and a second release liner was placed onthe binding material, with the siliconized side of the release linerfacing the binding material. A roller was passed over the second releaseliner pressing the binding material into the warm wax of the backinglayer. The resultant set (first release liner/backing layer/bindingmaterial/second release liner) was cooled to room temperature to form acomposition wherein a second part of the binding material wassubstantially invested in the backing layer. TABLE 4 Oral Care LayerFormulation Item Brand Name Supplier Percentage PolyvinylpyrrolidoneKollidone 90 BASF 58% K90 (PVP90) Polyethylene Glycol Carbowax UnionCarbide 30% 400 Polyethylene Glycol 400 Acrylic acid esters EudragitL100/55 Rohm America 12%

The oral care layer was produced as follows. The Kollidone 90 andEudragit L100/55 powders were mixed and blended with the polyethyleneglycol 400 (“PEG 400”) using a hotmelt-mixing procedure at 140° C. in astandard hotmelt mixer-extruder. The blend was extruded at 140° C.through a slot die spaced at 0.25 mm (10 mils) width using a singlescrew extruder, to obtain a film of about 0.38 mm (15 mils) thick. Theextrudate was collected on a siliconized release liner using standardpost-extrusion collecting equipment.

The oral care agent (an aqueous hydrogen peroxide solution) was added tothe oral care layer, and the oral care layer was laminated to thebinding material, as follows. A 35-50% hydrogen peroxide solution wasprinted onto the binding material side of the backing layer/bindingmaterial composition in a controlled process, such that the amount ofhydrogen peroxide solution printed onto the binding material wasequivalent to 3-10% of oral care layer. The melted Kollidone 90-EudragitL100/55-polyethylene glycol 400 blend was extruded on top of thehydrogen peroxide solution printed onto the binding material. The meltedblend absorbed the hydrogen peroxide solution as it was cooled, and inthe process adhered itself into and onto the binding material.

An optional scrim was embedded in the oral care layer as follows.DELNET® non-woven polyolefin fabric scrim (DelStar Technologies, Inc.,Middletown, Del.) was placed over the aqueous hydrogen peroxide solutionwhich had been printed onto the non-woven. The melted Kollidone90-Eudragit L100/55-polyethylene glycol 400 blend was extruded on top ofthe scrim. The melted blend flowed through and around the voids in thescrim, so that the scrim was entirely surrounded by the melted blend.Upon cooling and solidification of the melted blend, the scrim wasembedded within the oral care layer. The melted blend also absorbed thehydrogen peroxide solution as it cooled, and in the process adhereditself to the binding material.

After the backing and oral care layers were formed with the bindingmaterial as described above, devices of the invention were cut to thedesired size and shape and vacuum formed on a forming die. The overallthickness of the device was about 0.51 mm-0.61 mm (20-24 mils).

All documents referred to herein are incorporated by reference. Whilethe present invention has been described in connection with thepreferred embodiments and the various figures, it is to be understoodthat other similar embodiments may be used or modifications andadditions made to the described embodiments for performing the samefunction of the present invention without deviating therefrom.Therefore, the present invention should not be limited to any singleembodiment, but rather should be construed in breadth and scope inaccordance with the recitation of the appended claims.

1. A device for delivering an oral care agent, wherein the device issized to fit over a plurality of teeth in an upper or lower dental archin a subject, the device comprising: a permanently deformable backinglayer; a non-woven binding material comprising a first part and a secondpart; and an oral care layer comprising at least one oral care agent andat least one hydrophilic polymer, wherein the first part of the bindingmaterial is substantially invested in at least a portion of the oralcare layer, and the second part of the binding material is substantiallyinvested in at least a portion of the backing layer, and wherein theoral care layer has an adhesiveness when hydrated relative to thesurface of the teeth of the subject that is sufficient to retain thedevice on the user's teeth when placed thereon.
 2. The device of claim1, wherein the backing layer is from about 0.025 mm to about 0.508 mmthick.
 3. The device of claim 1, wherein the backing layer is from about0.125 mm to about 0.457 mm thick.
 4. The device of claim 1, wherein thebacking layer is about 0.38 mm thick.
 5. The device of claim 1, whereinthe backing layer comprises a non-polymeric material.
 6. The device ofclaim 5, wherein the non-polymeric material comprises a wax, a resin, ormixtures thereof.
 7. The device of claim 6, wherein the wax is selectedfrom the group consisting of a microcrystalline wax; a paraffin wax; asynthetic paraffin wax; and mixtures thereof.
 8. The device of claim 6,wherein the resin is a hydrocarbon resin.
 9. The device of claim 8,wherein the hydrocarbon resin is a water-white, clear cycloaliphatichydrocarbon resin.
 10. The device of claim 1 wherein the backing layeris colored.
 11. The device of claim 10 wherein the backing layer iscolored with at least one colorizing compound.
 12. The device of claim11 wherein the at least one colorizing compound is selected from thegroup consisting of FD&C Red No. 3; Food Red 17; Food Yellow 13; FD&CYellow No. 5; FD&C Yellow No. 6; FD&C Green No. 3; FD&C Blue No. 1; FD&CBlue No. 2; FD&C Red No. 40; Orange B; Citrus Red No. 2; andcombinations thereof.
 13. The device of claim 11 wherein the at leastone colorizing compound is selected from the group consisting of annattoextract; beta-apo-8′-carotenal; beta-carotene; beet powder;canthaxanthin; caramel color; carrot oil; cochineal extract (carmine);toasted, partially defatted, cooked cottonseed flour; ferrous gluconate;fruit juice; grape color extract; grape skin extract (enocianina);paprika; paprika oleoresin; riboflavin; saffron; turmeric; turmericoleoresin; vegetable juice; and combinations thereof.
 14. The device ofclaim 11 wherein the at least one colorizing compound is selected fromthe group consisting of titanium dioxide; chromium oxide greens;ultramarine blues and pinks; and ferric oxides.
 15. The device of claim11, wherein the dye comprises a dye-lake form.
 16. The device of claim15, wherein the dye-lake form is selected from the group consisting ofFD&C Green #1 lake; FD&C Blue #2 lake; FD&C R&D #30 lake; and FD&CYellow #15 lake.
 17. The device of claim 11, wherein the at least onecolorizing compound comprises about 0.05% to about 10% by weight of thebacking layer.
 18. The device of claim 17, wherein the at least onecolorizing compound comprises about 0.1% to about 5% by weight of thebacking layer.
 19. The device of claim 11, wherein the backing layercomprises multiple colors.
 20. The device of claim 19, wherein themultiple colors comprise a pattern.
 21. The device of claim 11, whereinthe backing layer further comprises glitter particles.
 22. The device ofclaim 1, wherein the backing layer is embedded or decorated withdecorative items.
 23. The device of claim 11, wherein the backing layeris embedded or decorated with decorative items.
 24. The device of claim1, wherein the backing layer displays letters, words, or images.
 25. Thedevice of claim 11, wherein the backing layer displays letters, words,or images.
 26. The device of claim 1, wherein the binding material isselected from a group consisting of a polyolefin; polyester;polyurethane; polyamide; polyaramide; and glass.
 27. The device of claim26, wherein the binding material comprises a polypropylene.
 28. Thedevice of claim 27, wherein the binding material comprises a spun bondedpolypropylene.
 29. The device of claim 1, wherein the binding materialis from about 0.089 mm to about 0.279 mm thick.
 30. The device of claim29, wherein the binding material is from about 0.114 mm to about 0.203mm thick.
 31. The device of claim 30, wherein the binding material isabout 0.152 mm thick.
 32. The device of claim 1, wherein the bindingmaterial is colored.
 33. The device of claim 32 wherein the bindingmaterial is colored with at least one colorizing compound.
 34. Thedevice of claim 33 wherein the at least one colorizing compound isselected from the group consisting of FD&C Red No. 3; Food Red 17; FoodYellow 13; FD&C Yellow No. 5; FD&C Yellow No. 6; FD&C Green No. 3; FD&CBlue No. 1; FD&C Blue No. 2; FD&C Red No. 40; Orange B; Citrus Red No.2; and combinations thereof.
 35. The device of claim 33 wherein the atleast one colorizing compound is selected from the group consisting ofannatto extract; beta-apo-8′-carotenal; beta-carotene; beet powder;canthaxanthin; caramel color; carrot oil; cochineal extract (carmine);toasted, partially defatted, cooked cottonseed flour; ferrous gluconate;fruit juice; grape color extract; grape skin extract (enocianina);paprika; paprika oleoresin; riboflavin; saffron; turmeric; turmericoleoresin; vegetable juice; and combinations thereof.
 36. The device ofclaim 33 wherein the at least one colorizing compound is selected fromthe group consisting of titanium dioxide; chromium oxide greens;ultramarine blues and pinks; and ferric oxides.
 37. The device of claim33, wherein the dye comprises a dye-lake form.
 38. The device of claim37, wherein the dye-lake form is selected from the group consisting ofFD&C Green #1 lake; FD&C Blue #2 lake; FD&C R&D #30 lake; and FD&CYellow #15 lake.
 39. The device of claim 33, wherein the colorizingcompound comprises about 0.05 percent to about 10 percent by weight ofthe binding material.
 40. The device of claim 39, wherein the colorizingcompound comprises about 0.1 percent to about 5 percent by weight of thebinding material.
 41. The device of claim 33, wherein the bindingmaterial comprises multiple colors.
 42. The device of claim 1, whereinthe oral care layer is from about 0.025 mm to about 4 mm thick.
 43. Thedevice of claim 42, wherein the oral care layer is from about 0.125 mmto about 1.5 mm thick.
 44. The device of claim 43, wherein the oral carelayer is from about 0.25 mm to about 1.0 mm thick.
 45. The device ofclaim 44, wherein the oral care layer is about 0.3 mm thick.
 46. Thedevice of claim 1, wherein the adhesiveness of the oral care layer withrespect to the surface of the user's teeth is from about 200 N/m toabout 400 N/m.
 47. The device of claim 1, wherein the at least one oralcare agent is entrapped within the oral care layer.
 48. The device ofclaim 47, wherein the at least one oral care agent is released from thehydrophilic polymer upon hydration of the oral care layer.
 49. Thedevice of claim 1, wherein the at least one oral care agent is activatedupon hydration of the oral care layer.
 50. The device of claim 1 whereinthe oral care layer comprises a pressure-sensitive adhesive comprisingat least one oral care agent, at least one hydrophilic polymer, and atleast one water-soluble plasticizer that is miscible with thehydrophilic polymer.
 51. The device of claim 50 wherein the at least onehydrophilic polymer has a hydrophilicity as measured by water uptake ofgreater than about 25%.
 52. The device of claim 51 wherein the at leastone hydrophilic polymer has a glass transition temperature T(g) ormelting point T(m) higher than about 25° C. and lower than about 120° C.53. The device of claim 52, wherein the at least one hydrophilic polymerhas a glass transition temperature T(g) or melting point T(m) higherthan about 30° C. and lower than about 100° C.
 54. The device of claim50 wherein the at least one hydrophilic polymer is selected from thegroup consisting of polysaccharides; water-soluble synthetic polymers;polypeptides; and natural gums.
 55. The device of claim 50 wherein theat least one hydrophilic polymer is selected from the group consistingof starches and starch derivatives; polyvinyl pyrrolidone; polyvinylalcohol; hydroxypropyl cellulose; sodium carboxymethyl cellulose;polyethylene oxide; polyacrylic acid; polyacrylates; carboxylic acidpolymers; xanthan gum; karaya gum; and gelatin.
 56. The device of claim50 wherein the at least one plasticizer is liquid at room temperatureand has a boiling point higher than about 80° C.
 57. The device of claim56 wherein the at least one plasticizer is selected from the groupconsisting of glycerins; sorbitol; glycols; polysorbate 80; triethyltitrate; acetyl triethyl titrate; and tributyl titrate.
 58. The deviceof claim 50, wherein the oral care layer comprises at least onecrosslinked or non-crosslinked polymer selected from the groupconsisting of 2-acrylamido-2-methyl-propanesulfonic acid; polyvinylpyrrolidone; polyethylene oxide; acrylates; polyvinyl alcohol; andcarboxylic acid polymers.
 59. The device of claim 58, wherein the oralcare layer comprises crosslinked or non-crosslinked2-acrylamido-2-methyl-propanesulfonic acid.
 60. The device of claim 58,wherein the oral care layer comprises crosslinked or non-crosslinkedpolyvinyl pyrrolidone.
 61. The device of claim 1, wherein the oral carelayer is a sustained release oral care layer.
 62. The device of claim50, wherein the oral care layer is a sustained release oral care layer.63. The device of claim 60, wherein the oral care layer is a sustainedrelease oral care layer.
 64. The device of claim 63 wherein thesustained-release oral care layer releases the at least one oral careagent at a rate of approximately 0.2 mg/cm²-min to 1 mg/cm²-min.
 65. Thedevice of claim 1, wherein the amount of the at least one oral careagent in the oral care layer is about 0.01% to about 40%.
 66. The deviceof claim 65, wherein the amount of the at least one oral care agent inthe oral care layer is about 0.1% to about 20%.
 67. The device of claim66, wherein the amount of the at least one oral care agent in the oralcare layer is about 0.5% to about 14%.
 68. The device of claim 67,wherein the amount of the at least one oral care agent in the oral carelayer is about 1% to about 10%.
 69. The device of claim 1, wherein theat least one oral care agent is a pharmaceutically active agent or acosmetically active agent.
 70. The device of claim 69, wherein thepharmaceutically active agent is selected from the group consisting of anon-steroidal anti-inflammatory/analgesic; a steroidal anti-inflammatoryagent; a local anesthetic; a bactericide/disinfectant; an antibiotic; anantifungal; a tooth desensitizing agent; a fluoride anticavity/antidecayagent; an anti-tartar/anti-calculus agent; an enzyme which inhibits theformation of plaque, calculus or dental caries; and a nutritionalsupplement for local delivery to the teeth and surrounding tissue. 71.The device of claim 70, wherein the non-steroidalanti-inflammatory/analgesic agent is selected from the group consistingof acetaminophen; methyl salicylate; monoglycol salicylate; aspirin;mefenamic acid; flufenamic acid; indomethacin; diclofenac; alclofenac;diclofenac sodium; ibuprofen; flurbiprofen; fentizac; bufexamac;piroxicam; phenylbutazone; oxyphenbutazone; clofezone; pentazocine;mepirizole; and tiaramide hydrochloride.
 72. The device of claim 70,wherein the steroidal anti-inflammatory agent is selected from the groupconsisting of hydrocortisone; prednisolone; dexamethasone; triamcinoloneacetonide; fluocinolone acetonide; hydrocortisone acetate; prednisoloneacetate; methylprednisolone; dexamethasone acetate; betamethasone;betamethasone valerate; flumetasone; flourometholone; budesonide; andbeclomethasone dipropionate.
 73. The device of claim 70, wherein thelocal anesthetic is selected from the group consisting of dibucainehydrochloride; dibucaine; lidocaine hydrochloride; lidocaine;benzocaine; p-buthylaminobenzoic acid 2-(diethylamino) ethyl esterhydrochloride; procaine hydrochloride; tetracaine hydrochloride;chloroprocaine hydrochloride; oxyprocaine hydrochloride; mepivacaine;cocaine hydrochloride; and piperocaine hydrochloride.
 74. The device ofclaim 70, wherein the bactericide/disinfectant is selected from thegroup consisting of thimerosol; phenol; thymol; benzalkonium chloride;benzethonium chloride; chlorhexidine; providone iodide; cetylpyridiniumchloride; eugenol, and trimethylammonium bromide.
 75. The device ofclaim 70, wherein the antibiotic is selected from the group consistingof penicillin; meticillin; oxacillin; cefalotin; cefaloridin;erythromycin; lincomycin; tetracycline; chlortetracycline;oxytetracycline; metacycline; chloramphenicol; kanamycin; streptomycin;gentamicin; bacitracin; and cycloserine.
 76. The device of claim 70,wherein the antifungal drug is selected from the group consisting ofamphotericin; clotrimazole; econazole nitrate; fluconazole;griseofulvin; itraconazole; ketoconazole; miconazole; nystatin;terbinafine hydrochloride; undecenoic acid; and zinc undecenoate. 77.The device of claim 70, wherein the tooth-desensitizing agent isselected from the group consisting of potassium nitrate and strontiumchloride.
 78. The device of claim 70, wherein the fluorideanticavity/antidecay agent is selected from the group consisting ofsodium fluoride, potassium fluoride and ammonium fluoride.
 79. Thedevice of claim 70, wherein the anti-tartar/anti-calculus agents isselected from the group consisting of phosphates; pyrophosphates,polyphosphates, polyphosphonates; linear carboxylic acids; sodium zinccitrate; and mixtures thereof.
 80. The device of claim 70, wherein theenzyme which inhibits the formation of plaque, calculus or dental cariesis selected from the group consisting of proteases; lipases;dextranases, glucanohydrolases, endoglycosidases, mucinases; amylases;and mixtures thereof.
 81. The device of claim 70, wherein thenutritional supplement for local delivery to the teeth and surroundingtissue is a vitamin or mineral.
 82. The device of claim 81, wherein thenutritional supplement for local delivery to the teeth and surroundingtissue is a vitamin selected from the group consisting of vitamin C;vitamin D; thiamine; riboflavin; calcium pantothenate; niacin; folicacid; nicotinamide; pyridoxine; cyanocobalamin; para-aminobenzoic acid;bioflavonoids; and mixtures thereof.
 83. The device of claim 81, whereinthe nutritional supplement for local delivery to the teeth andsurrounding tissue is a mineral selected from the group consisting ofcalcium; phosphorus; fluoride; zinc; manganese; potassium; and mixturesthereof.
 84. The device of claim 69, wherein the cosmetically activeagent is selected from the group consisting of a breath freshener; atooth whitening agent; and a tooth coloring or tinting agent.
 85. Thedevice of claim 84, wherein the tooth whitening agent is selected fromthe group consisting of peroxides; metal chlorites; perborates;percarbonates; peroxyacids; and combinations thereof.
 86. The device ofclaim 85, wherein the tooth whitening agent is a peroxide selected fromthe group consisting of hydrogen peroxide; calcium peroxide; carbamideperoxide; and mixtures thereof.
 87. The device of claim 85, wherein thetooth whitening agent is a metal chlorite selected from the groupconsisting of calcium chlorite; barium chlorite; magnesium chlorite;lithium chlorite; sodium chlorite; and potassium chlorite; hypochloriteand chlorine dioxide.
 88. The device of claim 85, wherein theconcentration of tooth whitening agent in the oral care layer is about0.01% to about 40%.
 89. The device of claim 86, wherein the peroxidecompound in the oral care layer is equivalent to about 0.1% to about 20%hydrogen peroxide.
 90. The device of claim 89, wherein the peroxidecompound in the oral care layer is equivalent to about 0.5% to about 13%hydrogen peroxide.
 91. The device of claim 90, wherein the peroxidecompound in the oral care layer is equivalent to about 1% to about 10%hydrogen peroxide.
 92. The device of claim 91, wherein the peroxidecompound in the oral care layer is equivalent to about 6-9% hydrogenperoxide.
 93. The device of claim 86, wherein the amount of hydrogenperoxide in the oral care layer is from about 0.1% to about 30%.
 94. Thedevice of claim 93, wherein the amount of hydrogen peroxide in the oralcare layer is from about 3% to about 20%.
 95. The device of claim 94,wherein the amount of hydrogen peroxide in the oral care layer is fromabout 6% to about 12%.
 96. The device of claim 1, wherein at least onelayer further comprises a colorizing compound; food additive; flavorant;sweetener; or preservative.
 97. The device of claim 96, wherein theflavorant is selected from the group consisting of wintergreen;peppermint; spearmint; menthol; fruit flavors; vanilla; cinnamon;spices; flavor oils; oleoresins; and mixtures thereof.
 98. The device ofclaim 96, wherein the sweetener is selected from the group consisting ofsucrose; fructose; aspartame; xylitol; and saccharine.
 99. The device ofclaim 1, wherein: i) the backing layer comprises 50% microcrystallinewax, 15% paraffin wax; and 35% hydrocarbon resin; ii) the bindingmaterial comprises a spun bonded polypropylene; and iii) the oral carelayer comprises 6-9% hydrogen peroxide, 30-40% polyvinylpyrrolidone K90,7-15% polyethylene glycol 400; and 15-20% methacrylic acid-ethylacrylate copolymer (1:1).
 100. The device of claim 99, wherein thebacking layer is colored.
 101. The device of claim 1, further comprisinga release liner or covering over the oral care layer.
 102. The device ofclaim 1, further comprising a scrim embedded in the oral care layer.103. The device of claim 99, further comprising a scrim embedded in theoral care layer.
 104. The device of claim 103, wherein the scrimcomprises one or more of woven, non-woven or perforated sheetlikematerials.
 105. The device of claim 104, wherein the woven materials ofthe scrim are selected from the group consisting of cotton; apolyolefin; polyester; polyurethane; polyamide; polyaramide; and glass.106. The device of claim 104, wherein the non-woven material of thescrim is selected from the group consisting of a polyolefin; polyester;polyurethane; polyamide; polyaramide; and glass.
 107. The device ofclaim 104, wherein the perforated material of the scrim comprises finepitch polypropylene net.
 108. The device of claim 102, wherein the scrimcomprises a non-woven polyolefin.
 109. The device of claim 103, whereinthe scrim comprises a non-woven polyolefin.
 110. The device of claim 1which has a “J”, “reversed J”, or “C” shape when viewed incross-section.
 111. The device of claim 1 which is sized to fit theprimary, mixed or permanent dentition of a human being.
 112. The deviceof claim 1 which is of sufficient length and width to cover the facialsurface, crowns and at least partially cover the lingual surface of theincisors in an upper or lower dental arch of a human being.
 113. Thedevice of claim 1 which is of sufficient length and width to cover thefacial surface, crowns and at least partially cover the lingual surfaceof the anterior teeth in an upper or lower dental arch of a human being.114. The device of claim 1 which is of sufficient length and width tocover the facial surface, crowns and at least partially cover thelingual surface of the anterior and posterior teeth in an upper or lowerdental arch of a human being.
 115. The device of claim 1 designed to fitthe upper dental arch of a human being, wherein the device is about 7 cmto about 9 cm in length, and about 0.8 cm to about 2.5 cm in width. 116.The device of claim 1 designed to fit the lower dental arch of a humanbeing, wherein the device is about 4 cm to about 6 cm in length, andabout 1 cm to about 2 cm in width.
 117. The device of claim 1, whereinthe device, when viewed in plan view, is bent into an essentiallyhorseshoe shape that generally matches the catenary arch of a humanbeing.
 118. The device of claim 1 further comprising one or morenotches.
 119. The device of claim 1, wherein the device is substantiallynon-flat.
 120. A method for delivering an oral care agent to the teethin an upper or lower dental arch in a subject, which teeth are in needof treatment, comprising: 1) providing the device of claim 1; 2) wettingthe teeth or the oral care layer of the device; 3) placing the deviceover the teeth of a dental arch which are in need of treatment, and 4)conforming the device to the teeth and surrounding tissue by manualpressure so that the oral care layer is in contact with at least thefacial surface of the teeth to be treated.
 121. The method of claim 120,wherein the treatment comprises the treatment of an undesirablephysiological condition.
 122. The method of claim 121, wherein theundesirable physiological condition is selected from the groupconsisting of halitosis; periodontal and oral infections; periodontallesions; dental caries or decay; and gingivitis.
 123. The method ofclaim 120, wherein the oral care layer comprises a pressure-sensitiveadhesive comprising at least one oral care agent, at least onehydrophilic polymer, and at least one water-soluble plasticizer that ismiscible with the hydrophilic polymer.
 124. The method of claim 123,wherein the at least one hydrophilic polymer has a hydrophilicity asmeasured by water uptake of greater than about 25%.
 125. The method ofclaim 124, wherein the at least one hydrophilic polymer has a glasstransition temperature T(g) or melting point T(m) higher than about 25°C. and lower than about 120° C.
 126. The method of claim 125, whereinthe oral care layer comprises at least one crosslinked ornon-crosslinked polymer selected from the group consisting of2-acrylamido-2-methyl-propanesulfonic acid; polyvinyl pyrrolidone;polyethylene oxide; acrylates; polyvinyl alcohol; and carboxylic acidpolymers.
 127. The method of claim 126, wherein the oral care layercomprises crosslinked or non-crosslinked2-acrylamido-2-methyl-propanesulfonic acid.
 128. The method of claim126, wherein the oral care layer comprises crosslinked ornon-crosslinked polyvinyl pyrrolidone.
 129. The method of claim 120,wherein the oral care layer is a sustained release oral care layer. 130.The method of claim 128, wherein the oral care layer is a sustainedrelease oral care layer.
 131. The method of claim 130, wherein thesustained-release oral care layer releases the at least one oral careagent at a rate of approximately 0.2 mg/cm² -min to 1 mg/cm²-min. 132.The method of claim 120, wherein the treatment comprises a cosmetictreatment.
 133. The method of claim 120, wherein the device is left onthe teeth for about 15 minutes to about 4 hours.
 134. The method ofclaim 133, wherein the device is left on the teeth for about 30 minutesto about 1 hour.
 135. A method for delivering a tooth whitening agent tothe teeth in an upper or lower dental arch in a subject comprising: 1)providing the device of claim 1, wherein the oral care agent is a toothwhitening agent; 2) wetting the teeth or the oral care layer of thedevice; 3) placing the device over the teeth of a dental arch, and 4)conforming the device to the teeth and surrounding tissue by manualpressure so that the oral care layer is in contact with at least thefacial surface of the teeth.
 136. The method of claim 135, wherein theoral care layer comprises a pressure-sensitive adhesive comprising atleast one tooth whitening agent, at least one hydrophilic polymer, andat least one water-soluble plasticizer that is miscible with thehydrophilic polymer.
 137. The method of claim 136, wherein the at leastone hydrophilic polymer has a hydrophilicity as measured by water uptakegreater than about 25%.
 138. The method of claim 137, wherein the atleast one hydrophilic polymer has a glass transition temperature T(g) ormelting point T(m) higher than about 25° C. and lower than about 120° C.139. The method of claim 138, wherein the oral care layer comprises atleast one crosslinked or non-crosslinked polymer selected from the groupconsisting of 2-acrylamido-2-methyl-propanesulfonic acid; polyvinylpyrrolidone; polyethylene oxide; acrylates; polyvinyl alcohol; andcarboxylic acid polymers.
 140. The method of claim 139, wherein the oralcare layer comprises crosslinked or non-crosslinked2-acrylamido-2-methyl-propanesulfonic acid.
 141. The method of claim139, wherein the oral care layer comprises crosslinked ornon-crosslinked polyvinyl pyrrolidone.
 142. The method of claim 135,wherein the oral care layer is a sustained release oral care layer. 143.The method of claim 141, wherein the oral care layer is a sustainedrelease oral care layer.
 144. The method of claim 143, wherein thesustained-release oral care layer releases the at least one toothwhitening agent at a rate of approximately 0.2 mg/cm²-min to 1mg/cm²-min.
 145. The method of claim 135, wherein the device is left onthe teeth for about 15 minutes to about 4 hours.
 146. The method ofclaim 135, wherein the device is left on the teeth for about 30 minutesto about 1 hour.
 147. The method of claim 135, wherein the toothwhitening agent is selected from the group consisting of peroxides;metal chlorites; perborates; percarbonates; peroxyacids; andcombinations thereof.
 148. The method of claim 147, wherein the toothwhitening agent is a peroxide selected from the group consisting ofhydrogen peroxide; calcium peroxide; carbamide peroxide; and mixturesthereof.
 149. The method of claim 147, wherein the tooth whitening agentis a metal chlorite selected from the group consisting of calciumchlorite; barium chlorite; magnesium chlorite; lithium chlorite; sodiumchlorite; and potassium chlorite; hypochlorite and chlorine dioxide.150. The method of claim 135, wherein the concentration of toothwhitening agent in the oral care layer is about 0.01% to about 40%. 151.The method of claim 148, wherein the peroxide compound in the oral carelayer provides an amount of peroxide equivalent to about 0.1% to about20% of hydrogen peroxide.
 152. The method of claim 148, wherein theperoxide compound in the oral care layer provides an amount of peroxideequivalent to about 0.5% to about 13% of hydrogen peroxide.
 153. Themethod of claim 148, wherein the peroxide compound in the oral carelayer provides an amount of peroxide equivalent to about 1% to about 10%of hydrogen peroxide.
 154. The method of claim 148, wherein the peroxidecompound in the oral care layer provides an amount of peroxideequivalent to about 6% of hydrogen peroxide.
 155. The method of claim148, wherein the amount of hydrogen peroxide in the oral care layer isfrom about 0.1% to about 30%.
 156. The method of claim 148, wherein theamount of hydrogen peroxide in the oral care layer is from about 3% toabout 20%.
 157. The method of claim 148, wherein the amount of hydrogenperoxide in the oral care layer is from about 6% to about 12%.
 158. Amethod of making the device of claim 1, comprising the steps of: 1)providing a permanently deformable backing layer, an oral care layer,and a non-woven binding material, wherein the binding material comprisesa first part and a second part; 2) integrally coupling at least aportion of the backing layer with the second part of the bindingmaterial; 3) extruding an oral care layer onto the first part of thebinding material such that at least a portion of the oral care layer isintegrally coupled with the first part of the binding material.
 159. Themethod of claim 158, in which an aqueous solution of the oral care agentis printed onto the binding material prior to extruding the oral carelayer onto the binding material.
 160. The method of claim 158, furthercomprising placing a scrim on the binding material before extruding theoral care layer onto the binding material.
 161. The method of claim 160,wherein the scrim comprises a non-woven polyolefin.